NZ754292B2 - Systems for selecting a time reference - Google Patents
Systems for selecting a time reference Download PDFInfo
- Publication number
- NZ754292B2 NZ754292B2 NZ754292A NZ75429214A NZ754292B2 NZ 754292 B2 NZ754292 B2 NZ 754292B2 NZ 754292 A NZ754292 A NZ 754292A NZ 75429214 A NZ75429214 A NZ 75429214A NZ 754292 B2 NZ754292 B2 NZ 754292B2
- Authority
- NZ
- New Zealand
- Prior art keywords
- time
- time reference
- signal
- coprocessing
- sfp
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
- G06F21/30—Authentication, i.e. establishing the identity or authorisation of security principals
- G06F21/31—User authentication
- G06F21/34—User authentication involving the use of external additional devices, e.g. dongles or smart cards
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0685—Clock or time synchronisation in a node; Intranode synchronisation
- H04J3/0697—Synchronisation in a packet node
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/02—Details
- H04L12/10—Current supply arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L63/00—Network architectures or network communication protocols for network security
- H04L63/08—Network architectures or network communication protocols for network security for authentication of entities
- H04L63/0876—Network architectures or network communication protocols for network security for authentication of entities based on the identity of the terminal or configuration, e.g. MAC address, hardware or software configuration or device fingerprint
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L63/00—Network architectures or network communication protocols for network security
- H04L63/12—Applying verification of the received information
- H04L63/123—Applying verification of the received information received data contents, e.g. message integrity
Abstract
system includes a router to receive and transmit data packets; a switch coupled to the router; a time reference generator coupled to the router; a plurality coprocessing cards coupled in communication with the switch and the time reference generator; and a plurality of small form pluggable time modules coupled to the plurality coprocessing cards. Each coprocessing card includes a plurality of multiplexers coupled together to receive and select one of a plurality of time reference signals. The time reference generator generates an external time reference signal communicated to each of the plurality of small form pluggable time modules that can be selected from amongst the plurality of time reference signals dules coupled to the plurality coprocessing cards. Each coprocessing card includes a plurality of multiplexers coupled together to receive and select one of a plurality of time reference signals. The time reference generator generates an external time reference signal communicated to each of the plurality of small form pluggable time modules that can be selected from amongst the plurality of time reference signals
Description
Atty. Ref.: 2030P010NZD3
SYSTEMS
FOR SELECTING
TIME REFERENCE
Inventors:
David Earl
Stuart Wilson
Prepared by:
Alford Law Group, Inc.
23052H Alicia Parkway, No. 201
Mission Viejo, CA 92692
Tel: (949) 595-0120
Atty. Ref.: 2030P010NZD3
SYSTEMS FOR SELECTING A TIME REFERENCE
CROSS REFERENCE
This patent application claims the benefit of U.S. Provisional Patent Application No.
62/048,098 entitled PLUGGABLE TIME SIGNAL ADAPTER MODULES FOR SELECTING
A TIME REFERENCE INTERFACE filed on September 09, 2014 by inventors David Earl et al.
This specification relates to more than one invention. Claims to the inventions can be found in
this specification and those of the parent cases NZ 735955, NZ718499 and NZ 631269.
FIELD
The embodiments generally relate to time reference signal interconnection to
networking equipment.
BACKGROUND
Networking equipment often has internal clocks to indicated date and time for files
and other information. However, date and time of internal clocks may not be accurate for some
applications. It is often desirable for networking equipment to have a more accurate date and
time.
A time reference signal may be used to provide a more accurate date and time to
networking equipment. The type of time reference signal and the means of communicating the
time reference signal to networking equipment can vary. Certain networking equipment may
receive one type of time reference signal over a wire cable, for example. Other networking
equipment may receive a different time reference signal over an optical cable, for example.
Integrating the different networking equipment with different types of time reference signals into
a network can be challenging.
It is desirable to provide a flexible approach to communicating time reference
signals to networking equipment.
It is an object of the invention to at least go some way to meeting this need; and/or
to provide a system and/or to at least provide the public with a useful choice.
Atty. Ref.: 2030P010NZD3
BRIEF SUMMARY
In a first aspect the present invention provides a system comprising:
a router to receive and transmit data packets;
a switch coupled to the router;
a time reference generator coupled to the router;
a plurality of coprocessing cards coupled in communication with the switch and the
time reference generator, each coprocessing card includes a plurality of multiplexers coupled in
communication together, wherein the plurality of multiplexers of each coprocessing card to
receive a plurality of differing time reference signals and select one as a selected time reference
signal of the coprocessing card;
a plurality of small form pluggable time modules coupled to the plurality of
coprocessing cards;
wherein the switch receives data signal packets and routes the data signal packets to
the plurality of coprocessing cards for processing; and
wherein the time reference generator generates an external time reference signal as
one of the plurality of differing time reference signals, the external time reference signal is
communicated to each of the plurality of small form pluggable time modules capable of being
selected by the plurality of multiplexers as the selected time reference signal of the coprocessing
card.
In an embodiment the switch routes copies of data signal packets in a load balanced
manner to each of the plurality of coprocessing cards.
In an embodiment the plurality of small form pluggable time modules are further
coupled to the switch to receive time signal packets from the time reference generator.
In an embodiment each of the plurality of small form pluggable time modules are
electro-optical small form pluggable time modules, and the system further comprises:
a plurality of optical cables coupled to and between the switch and the plurality of
electro-optical small form pluggable time modules.
Atty. Ref.: 2030P010NZD3
In an embodiment each of the plurality of small form pluggable time modules are
electrical small form pluggable time modules, and the system further comprises:
a plurality of wired Ethernet cables coupled to and between the switch and the
plurality of electrical small form pluggable time modules.
In an embodiment further comprising: a splitter coupled to the time reference
generator to split an external time reference signal from the time reference generator into a
plurality of external time reference signals;
wherein the plurality of small form pluggable time modules are respectively coupled
to the splitter to receive one of the plurality of external time reference signals.
In an embodiment each of the plurality of small form pluggable time modules are
electrical small form pluggable time modules, and the system further comprises:
a plurality of wired Ethernet cables coupled to and between the switch and the
plurality of electrical small form pluggable time modules.
In an embodiment each of the plurality of small form pluggable time modules are
optical small form pluggable time modules, and the system further comprises:
a plurality of optical cables coupled to and between the switch and the plurality of
optical small form pluggable time modules.
In an embodiment an internal generated clock generated by the coprocessing card is
another one of the plurality of time reference signals that can be selected by the plurality of
multiplexers as the selected time reference signal of the coprocessing card.
In an embodiment a card specific internal time reference signal generated by the
coprocessing card is another one of the plurality of time reference signals that can be selected by
the plurality of multiplexers as the selected time reference signal of the coprocessing card.
In an embodiment an internal universal time reference signal generated by the
coprocessing card is another one of the plurality of time reference signals that can be selected by
the plurality of multiplexers as the selected time reference signal of the coprocessing card.
Atty. Ref.: 2030P010NZD3
In an embodiment a high resolution internal time reference signal generated by the
coprocessing card is another one of the plurality of time reference signals that can be selected by
the plurality of multiplexers as the selected time reference signal of the coprocessing card.
In an embodiment the selected time reference signal is used by the coprocessing
card to time stamp data packets with a time and date.
The invention is defined in the claims that follow at the end of the specification.
In the description in this specification reference may be made to subject matter
which is not within the scope of the claims of the current application. That subject matter should
be readily identifiable by a person skilled in the art and may assist in putting into practice the
invention as defined in the claims of this application.
BRIEF DESCRIPTIONS OF THE DRAWINGS
Figure 1A is a block diagram of a networking system with a plurality of equipment
racks having networking equipment and a time reference generator.
Figure 1B is a block diagram of a portion of a networking system illustrating a time
reference generator from which a time reference signal propagates through a splitter and over
dedicated cables to networking equipment.
Figure 1C is a block diagram of a portion of a networking system illustrating a time
reference generator that packetizes a time reference signal into an Ethernet packet to form a time
reference signal packet that is then propagated through switches and cables to networking
equipment.
Figure 2 is a block diagram of a server with a plurality of daughter cards with one or
more of the daughter cards receiving a time reference signal.
Figure 3A is a diagram of a daughter card with a plurality of small form-factor
pluggable (SFP) ports with one SFP port being used to receive a time reference signal.
Figure 3B is a perspective view of a daughter card with SFP ports including female
SFP sockets and EMI cages mounted thereto in a column near an edge.
Atty. Ref.: 2030P010NZD3
Figure 4 is a functional block diagram of a time signal selection circuit to select one
of a plurality of time reference signals that may be used by the daughter card to synchronize the
networking equipment and time stamp data packets.
Figure 5 is a schematic diagram of how a male SFP connector of the SFP time signal
adapter couples a time reference signal to the female SFP socket of a daughter card and the
integrated module mounted thereto.
Figure 6 is a side view of a serial differential cable, an SFP time signal adapter, and
an SFP port of the daughter card being coupled together.
Figure 7 is a cross-sectional side view of the serial differential cable, the SFP time
signal adapter, and the SFP port of the high speed networking daughter card coupled together.
Figure 8 is an exploded view of a SFP time signal adapter with a male SFP
connector at one end and a serial differential cable connector at an opposite end to couple to a
serial differential cable.
Figure 9 is a perspective view of the SFP time signal adapter of Figure 8 without the
cover/housing assembled together.
Figure 10A is a schematic diagram of an SFP time signal adapter module for
differential time signals over a serial differential cable.
Figure 10B is a schematic diagram of a differential receiver-transmitter circuit for an
SFP time signal adapter module receiving/transmitting modulated time signals over a cable .
Figure 10C is a block diagram of an SFP time signal adapter module for receiving
optical time reference signals over optical network cable.
Figure 10D is a block diagram of an SFP time signal adapter module for receiving
packetized time signals over wire network cable.
Figure 11A is a detailed waveform diagram illustrating components of a time signal.
Figure 11B are waveform diagrams to illustrate a modulated time signal.
Atty. Ref.: 2030P010NZD3
Figure 12 is a diagram of an Ethernet packet to illustrate how a time reference signal
is embedded in a packet for optical signal transmission over an optical fibre and electrical signal
transmission over Ethernet.
DETAILED DESCRIPTION
In the following detailed description of the embodiments, numerous specific details
are set forth in order to provide a thorough understanding. However, it will be apparent to one
skilled in the art that the embodiments may be practiced without these specific details. In other
instances well known methods, procedures, components, and circuits have not been described in
detail so as not to unnecessarily obscure other aspects.
Methods, apparatus and systems are disclosed for selectively interfacing different
time signals to network equipment in a storage area network. Time reference signals may be of
different protocols (e.g., Ethernet, IRIG-B) and different signal types such as analog, digital,
optical, and electrical signals. One of a plurality of SFP time signal adapter modules can be
selected to interface a time signal with one of the various protocols and one of the signal types to
a printed circuit board card with a time signal port so that the time reference signal can be
received.
Signal control and time stamp referencing in high speed communication connections
between networked equipment may be used to manage the synchronization of the signals
transmitted and received in a local area network. High speed networked devices that form
communication links with ten gigabit per second data rates can make the synchronization of
signals more challenging. It may be desirable to synchronize or time stamp (with a date and
time) various forms of signals generated by the various types of system infrastructure such as
analog, optical, Ethernet or a combination thereof. Providing a flexible way for networking
equipment to support the various forms of signals is desirable. A synchronizing time reference
signal may be communicated in various networks by using different forms of signals.
As demand for higher data rates has increased, there has been a desire to use high
speed communication connections between various networking equipment. Small form
pluggable (SFP) transmitter/receivers have become popular due to the demands for high speed
communication connections within a local area network. Various SFP module configurations
Atty. Ref.: 2030P010NZD3
can be used with a daughter card to support the various forms of signals that may be used within
a local area network. The daughter card and its integrated circuit(s) can process the signals to
provide time stamps and synchronization. It is desirable to lower costs and provide more flexible
options when providing a plurality of high speed data connections between network equipment.
Local Area Networks With Time Reference Signals
Referring now to Figure 1A, a block diagram of a networking system 100 is
illustrated. The networking system 100 includes a plurality of equipment racks 102A-102N, a
router 101, a time reference generator 107, and an aggregation switch 103. The aggregation
switch 103 couples the networking system 100 to the router 101 by a redundant interconnection
114. The router 101 is coupled to the internet 150 or other wide area network by interconnection
115.
The time reference generator 107 is coupled to the router 101 by a redundant
interconnection 117 and to the aggregation switch 103 by redundant interconnection 129. The
time reference generator 107 may optionally communicate with the internet 150 by
interconnection 121 for periodic communication with an external timekeeping resource. The
time reference generator 107 may periodically communicate with an external timekeeping
resource to synchronize and validate its own clock mechanism and baseline timekeeping
resources. Various time reference generators 107 may be used in a network and generate various
time signals that are distributed through the local area network. Additional connections may be
made to the time reference generator 107 to distribute a time signal to the various networking
equipment.
Each equipment rack 102A-102N includes networking equipment, such as network
switches, keyboard, video, and mouse (KVM) switches, storage area networking (SAN) devices,
and servers in whatever format, such as tower servers, rack servers, or blade servers. For
example, in Figure 1, each equipment rack 102A-102N includes one or more servers 106A-106S
coupled to a rack switch 104. Each rack switch 104 of each equipment rack 102A-102N is
coupled to the aggregation switch 103 by interconnection 112A-112N.
Atty. Ref.: 2030P010NZD3
Servers often provide a high performance centralized computer to which client
computers may communicate for information exchange and/or to execute software applications.
For example, a server may execute a backup application and backup the data of client computers
periodically to a SAN device. Servers may be located locally to client computers in
communication over a local area network (LAN) or remotely in communication over a wide area
network (WAN), such as the internet. SAN devices provide data storage using one or more types
of media formats. Network switches provide the switching fabric between servers and SAN
devices and a gateway to the wide area network.
Redundant cables 112A-112N provide the long distance high speed data connection
between each rack switch 104 and the aggregation switch 103. High volume cables 110A-110S,
couple the one or more networking equipment in each rack to the rack switch 104. The cable
connections 110A-110S are redundant as well, for reliability, in case one or the other cable
connection becomes faulty, and to allow for load balancing between the redundant connections.
In one embodiment, the one or more servers 106A-106S are legacy equipment, with
each server having a small form pluggable (SFP) connector to receive an SFP plug or SFP cable
connector from the cables 110A-110S. In an embodiment, the one or more servers 106A-106S
are updated to include a cable connector, replacing the SFP connectors. In the case of legacy
equipment, a legacy equipment adaptor may be provided and plug into the SFP connector of the
legacy equipment to couple to cable plugs or connectors of the cables 110A-110S.
Various time reference generators may be used within a local area network that
generate different signal types of a synchronizing time reference signal. For example, the time
reference generator may packetize the time signal within an Ethernet packet for distribution
throughout the local area network with optical signals and electrical signals. Alternatively, a
time signal may be directly distributed to networking equipment by using an unmodulated
differential data signal or a modulated differential data signal, for example.
Network Coprocessing Daughter Cards
Referring now to Figure 1B, a block diagram of a portion of a networking system in
a local area network is shown. The portion of the networking system includes the time reference
Atty. Ref.: 2030P010NZD3
generator 107, the router 101, the switch 103, a signal splitter 105, and a plurality of network
coprocessing daughter cards 222A-222N coupled together as shown. The plurality of network
coprocessing daughter cards 222A-222N may be installed into a motherboard of one or more of a
plurality of networking equipment. Each network coprocessing daughter card 222A-222N may
receive data signals and a time reference signal.
In some embodiments, the time reference generator 107 generates a time reference
signal that is directly distributed to the network equipment in the local area network. In some
embodiments, the time reference signal is a differential standard IRIG-B time signal that may
provide one signal pulse per second (PPS). Figure 11A illustrates details of a standard IRIG-B
time reference signal. A differential data signal is a true and inverted signal or a positive and
negative time signal. In another embodiment, the time reference signal is a modulated
differential standard IRIG-B time reference signal. Figure 11B illustrates how a standard IRIG-
B time reference signal may be modulated.
The time reference generator 107 is coupled to the router by interconnection 117.
The time reference generator 107 may optionally be coupled to the switch 103 by
interconnection 129. The time reference generator 107 is coupled to a signal splitter 105 by
interconnection 128. The signal splitter 105 is coupled to the network coprocessing daughter card
222A-222N by cables 372A-372N, SFP time signal adapter modules 360A-360N, and their
respective connectors. The SFP time signal adapter modules 360A-360N are coupled into a time
signal port 356E of each packet processing daughter card 222A-222N. A dedicated SFP time
signal port 356E for the time reference signal is used in this case due to the time reference signal
being a different type of signal than that being received at the data signal ports 356A-356D. A
dedicated SFP time signal port 356E also avoids interfering with the volume of data packet
traffic expected through the SFP data signal ports 356A-356D.
In one embodiment, the cables 372A-372N are Ethernet cables with male RJ45
connectors at each end. In this case, the signal splitter 105 has RJ45 female sockets into which
the mail RJ45 connectors at one end of the Ethernet cables 372A-372N can plug into. The SFP
time signal adapter modules 360A-360N have RJ45 female sockets into which the male RJ45
connectors at the opposite end of the Ethernet cables 372A-372N can plug into. Male SFP edge
connectors of the SFP time signal adapter modules 360A-360N are coupled into respective
Atty. Ref.: 2030P010NZD3
female SFP edge connectors 357E in SFP EMI cages of the time signal ports 356E of the
network coprocessing daughter card 222A-222N.
The time reference signal propagates from the time reference generator 107 to the
signal splitter 105. The signal splitter 105 splits the time reference signal so that it is multiplexed
out towards the plurality of network coprocessing daughter cards 222A-222N over the cables
372A-372N. The split time reference signals from the cables 372A-372N are coupled into the
SFP time signal adapter modules 360A-360N. The split time reference signal from the cables are
processed by the SFP time signal adapter modules 360A-360N into SFP signal levels and
coupled into the PCB cards 222A-222N. The SFP time signal adapter modules 360A-360N may
convert a differential serial data signal into a non-differential serial data signal with SFP
compatible signal levels. In embodiments, the SFP time signal adapter modules 360A-360N
may demodulate a modulated time reference signal into a non-modulated time reference signal.
In any case, the SFP time signal adapter modules 360A-360N receive and process the split time
reference signals from the splitter 105. In one embodiment, the split time reference signal is an
IRIG-B standard time reference signal clocked at one pulse per second time signal input from the
splitter 105.
Data signal packets propagate to the PCB cards 222A-222N to be processed by one
or more pieces of network equipment in the local area network. Data signal packets flow from
the router 101 to the switch 103 over redundant Ethernet cables 114. The switch 103 reads the
IP address and may route the data signal packets to the network equipment to which it is
addressed. The switch 103 may also route copies of data signal packets in a load balanced
manner to each of the PCB cards 222A-222N in network equipment (e.g., one or more of
equipment 106A-106S in one or more racks 102A-102N in Figure 1A) over cables 109A-109D.
In one embodiment, the cables 109A-109N are Ethernet cables with RJ-45 male connectors
coupled to each end. In one embodiment, the PCB cards 222A-222N include female RJ-45
sockets to receive the mail RJ-45 connectors. In an embodiment, the PCB cards 222A-222N
include SFP data ports 356A-356D with female SFP sockets 357A-357D to receive SFP data
signal adapter modules 361A-361D (collectively SFP data signal adapter modules 361).
Figures 1B-1C show SFP data signal adapter modules 361A-361D ready to plug
into the female SFP sockets 357A-357D and SFP data ports 356A-356D of the daughter card
Atty. Ref.: 2030P010NZD3
222A. The SFP data signal adapter modules 361A-361D are already plugged into female SFP
sockets 357A-357D and SFP data ports 356A-356D of the daughter cards 222B-222N.
In one case, the SFP data signal adapter modules 361A-361D (collectively referred
to by reference number 361 herein) include SFP optical sockets at one end to receive SFP optical
plugs of optical cables 109A-109D. In another embodiment, the SFP data signal adapter
modules 361 include female RJ-45 electrical sockets at one end to receive the male RJ-45
electrical connectors of electrical cables 109A-109D. Each of the SFP data signal adapter
modules 361 include a male SFP edge connector for plugging into the female SFP edge
connectors 357A-357D mounted to the PCBs 222A-222N within SFP EMI cages of the SFP data
ports 356A-356D. Whether cables 109A-109B are electrical cables or optical cables, data signal
packets without a received time stamp are carried between the switch 103 and the SFP data
signal adapter modules 361A-361D.
The SFP data signal adapter modules 361 process the data packets into data signals.
Data signals from the SFP data signal adapter modules 361 and a time reference signal from one
of the SFP time signal adapter modules 360A-360N (collectively referred to by reference number
360), are communicated to a data packet coprocessing circuit 352A-352N on each network
coprocessing daughter card 222A-222N. The data packet coprocessing circuits 352A-352N are
mounted to the daughter cards 222A-222N and coupled to the female SFP edge connectors
357A-357E by traces of the printed circuit board. The data packet coprocessing circuits 352A-
352N may be flexibly implemented by a field programmable gate array (FPGA).
The data packet processing circuit 352A-352N receives the time reference signal
and the data signals in serial form from the respective modules 360 and 361A-361D on each card
222A-222N. The data packet processing circuit 352A-352N may have a serializer/deserializer
(SERDES) to deserialize the date and time reference data of the serial signal into a parallel form.
For any acknowledgement or control signal to be sent back to the time reference generator 107,
the SERDES of the data packet processing circuit 352A-352N may serialize a data signal for
packetizing and transmitting/transmission back to the time signal reference generator 107.
In response to the time reference signal, the data packet coprocessing circuit 352A-
352N adds a date and a time (collectively referred to as a time stamp) to the data in the data
packet as they are received by each of the daughter cards 222A-222N. Time stamp logic 354A-
Atty. Ref.: 2030P010NZD3
354N (or time stamp instructions, in the case of software) in each data packet processing circuit
352A-352N adds the date and time as a time stamp to the data packet.
With a date and a time (collectively referred to as a time stamp) associated with the
data in the data packets, the data may be further processed by the data packet processing circuit
352A-352N and/or the networking equipment (e.g., servers 106A-106S) in which one or more of
the daughter cards 222A-222N may reside. The data and associated time stamp may be output
from the daughter cards 222A-222N as a digital output signal 111A-111N through a PCB edge
connector 250A-250N for further processing by the server. The daughter cards may also
packetize the data and associated time stamp together back into a time stamped data packet, such
as an Ethernet packet, and communicate it to other networking equipment within the local area
network.
A time reference generator may be used within a local area network that generates a
different signal type for a synchronizing time reference signal. A time reference generator may
packetize the time signal within an Ethernet packet for distribution throughout the local area
network with optical signals and/or electrical signals. The Standard for a Precision Clock
Synchronization Protocol for Networked Measurement and Control Systems published by the
Institute of Electrical and Electronic Engineers as IEEE 1588 standard, introduced a precision
time protocol (PTP) that was used to synchronize clocks throughout a computer network.
Referring now to Figure 1C, a portion of a networking system is illustrated with a
time reference generator 107’ that packetizes a time reference signal into an Ethernet packet to
form a time reference signal packet. The time reference signal packet can then be broadcast into
the local area network through one or more switches 103, interconnections/cables 129,160A-
160N, and SFP time signal adapter modules 358A-358N to the SFP time signal ports 356E of the
daughter cards 222A-222N in the various networking equipment. In this case, a dedicated SFP
time signal port 356E for time reference signal packets may be desirable to avoid interfering with
the expected volumes of data packet traffic through the SFP data signal ports 356A-356D.
The portion of the networking system illustrated in Figure 1C includes the router
101, the time reference generator 107’, and the switch 103 coupled together by interconnections
or cables 114,117,129. Interconnections or cables 160A-160N may be used to couple together
the switch 103 and SFP time signal adapter modules 358A-358N and carry the time reference
Atty. Ref.: 2030P010NZD3
signal packets between each. Interconnections or cables 110A-110D, for example, may be used
to couple together the switch 103 and SFP data signal adapter modules 361A-361D of each card
222A-222N and carry the data signal packets between each.
The cable 129 and/or cables 160A-160N may be wire Ethernet cables for
transmission of time reference signal packets via electrical signals or fibre optic cables for
transmission of time reference signal packets via optical signals. In one embodiment, the cables
160A-160N are Ethernet cables with RJ-45 male connectors attached to both ends of the cables.
In this case, the SFP time signal adapter modules 358A-358N include female RJ-45 sockets at
one end to receive the male RJ-45 connectors of electrical cables 160A-160N. In another
embodiment, the cables 160A-160N are fibre optical cables with SFP optical connectors at each
end. In this case, the SFP time signal adapter modules 358A-358N include SFP sockets at one
end to receive SFP plugs of optical cables 160A-160N. Whether optical or electrical signals,
each of the SFP time signal adapter modules 358A-358N include a male SFP edge connector for
plugging into the female SFP edge connectors 357E mounted to the PCBs 222A-222N within
SFP EMI cages of the SFP time signal port 356E. In either case, with a time reference signal
packet, the SFP time signal adapter modules 358A-358N may be similar to SFP data signal
adapter modules 361A-361D for the corresponding cable type.
The SFP time signal adapter modules 358A-358N may receive the time reference
signal packets, depacketize, and extract the date and time reference data therein. The date and
time reference data may be serially coupled into the data packet processing circuit 352A-352N of
each daughter card 222A-222N. The data packet processing circuit 352A-352N may have a
serializer/deserializer (SERDES) to deserialize the date and time reference data into a parallel
form for time stamping the data in data packets.
With a time stamp (including date and time) associated with the data in the data
packets, the data may be further processed by the data packet processing circuit 352A-352N
and/or the networking equipment (e.g., servers 106A-106S) in which one or more of the daughter
cards 222A-222N may reside. The data and associated time stamp may be output from the
daughter cards 222A-222N as a digital output signal 111A’-111N’ through a PCB edge
connector 250A-250N for further processing by one or more of the servers 106A-106S. The data
Atty. Ref.: 2030P010NZD3
and associated time stamp may be packeted together into a data packet, such as an Ethernet
packet, and communicated to other networking equipment within the local area network.
Referring now to Figure 2, a block diagram of one piece of networking equipment
106A (e.g., a server) is illustrated. The networking equipment 106A includes a motherboard 200
with a microprocessor 202, a memory 204, and a plurality of card connectors 206A-206N
coupled together by conductive wire traces 210 of a printed circuit board 201. The edge
connector 250A-250N of one or more networking daughter cards 222A-222N may be plugged
into one or more card connectors 206A-206N. In one embodiment, the daughter cards 222A-
222N may be peripheral component interconnect express (PCIe) cards having a PCIe bus with a
PCIe edge connector 250A-250N that plugs into a PCIe socket 206A-206N.
Flexible Time Signal Adaptation
Referring now to Figures 3A-3B, a networking daughter card 222 is illustrated
having an edge connector 250 that is pluggable into a socket 260 of the motherboard 200 of the
networking equipment. The networking daughter card 222 further includes a printed circuit
board 301 with the data packet processing circuit 352, a buffer memory 353, SFP data ports
356A-356D, and an SFP time port 356E coupled together by wire traces 354A-354D,355 of the
printed circuit board. The networking daughter card 222 may alternatively be referred to as a
networking card, networking coprocessor card, or network coprocessing card.
In one embodiment, the data packet processing circuit 352 is a field programmable
gated array (FPGA). In some embodiments, the buffer memory 353 is a random access memory
(RAM). Each of the SFP ports 356A-356D,356E includes a female SFP connector 357A-357E
coupled to the respective wire traces 354A-354D,355 and an SFP EMI cage mounted over the
female SFP connector. The data signals are coupled to the data packet processing circuit 352 by
the wire traces 354A-354D. The time reference signal is coupled to the data packet processing
circuit 352 by the wire traces 355.
The edge connector 250 of the card 222 includes a plurality of pads 302. The pads
302 of the edge connector 250 couple to the pads or pins of the female socket 260 of the system
200 motherboard. The data packet processing circuit 352 and the buffer memory 353 are
Atty. Ref.: 2030P010NZD3
coupled to the pads 302 of the edge connector 250. In this manner, signals can be routed
between the system motherboard 200 and the daughter card 222. With the daughter card 222
pluggable into the edge connector 250 of the mother board, it can be unplugged and removed
from the networking equipment so that a failing daughter card can be replaced or the daughter
card can be updated to a newer design.
The SFP data signal ports 356A-356D of the daughter card 222 receive the SFP data
signal adapter 361A-361D (e.g., see Figure 1B). As shown in Figure 3A, the SFP time signal
port 356E receives one of a plurality of different types of SFP time signal adapters modules
358,359,360 (e.g., see Figures 10A-10D).
One of a plurality of different SFP time signal adapter modules 358-360 can be
plugged into the SFP time signal port 356E and its SFP connector 357E. The different SFP time
signal adapter modules 358-360 are configured to receive the different time stamped reference
signals that are generated by different time reference generators (e.g., see generators 107,107’ of
Figure 1B-1C). The one SFP time signal adapter module may be selected by being compatible
with the type of time reference signal generated by the time reference generator 107,107’ of
Figures 1B and 1C.
Upon selection of the SFP time signal adapter module at a physical interface level, a
software driver may be used thereafter to configure each daughter card in the networking
equipment, such as daughter card 222 of Figure 3A, at a logical interface level to receive the
respective time reference signal from the selected SFP time signal adapter module. Accordingly,
a software driver executed by the networking equipment in which it resides, may configure the
data packet processing circuit 352 and the daughter card 222 to the type of SFP time signal
adapter module and the time reference signals that are to be received. The buffer memory 353 or
other storage device on the card 222 may be used to store initialization/management/control
software that is executable with the data packet processing circuit 352 to configure the circuit.
Alternatively with reference to Figure 2, memory 204 of the motherboard 200 may store the
software and be executed by the processor 202 to configure the respective cards 222A-222N.
Instead of forming a custom daughter card for each of the different types of time
reference signals, the various SFP time signal adapter modules can be used to flexibly adapt the
daughter card 222 to the time reference generator 107,107’ (Figures 1B and 1C) that is available
Atty. Ref.: 2030P010NZD3
in the local area network. In this manner, each daughter card (such as daughter card 222 of
Figure 3A) and the networking equipment into which it is installed can be backwardly and
forwardly compatible with the various types of time reference signals to be received from the
various time reference generators.
The various SFP time signal adapter modules further allow each daughter card and
networking equipment to be made in advance, regardless of the time signal generator that may be
already resident or selected for use in a local area network. Thus, the one or more daughter cards
222A-222N and the networking equipment in which they are resident can be ready and waiting
for orders and then delivered more quickly to a customer in response to the order.
The data packet processing circuit 352 may have circuits and/or execute software to
process the data packets and associate a date and time stamp with the data of each data packet
that is received over the data signal ports. With the data being associated with the time stamp, it
may then be further processed by the networking equipment in the local area network.
A time reference signal may be internally generated by networking equipment.
However, an internally generated time reference signal may not be as accurate as an external
time reference signal. Moreover, if a plurality of networking equipment is utilized within a local
area network, the internally generated time reference signal is likely to be out of synchronization
with an internally generated time reference signal of another piece of networking equipment in
the same local area network. Accuracy of a time reference signal, and date and time stamp
associated with data packets, may be improved by using a time reference signal generator and an
externally generated time reference signal that is broadcast or split to each of a plurality of
networking equipment. However, it may be desirable to make a daughter card flexible with the
capability of receiving internal time reference signals or external time reference signals and the
various types of each.
Referring now to Figure 4, a diagram of time signal selection logic 400 in the data
packet processing circuit 352 is shown. In some embodiments, the signal selection logic is
implemented by a field programmable gate array (FPGA). The time signal selection logic 400
includes a plurality of multiplexers (MUX) 480-482, and a configuration register 485 coupled
together. The configuration register 485 generates control or selection signals that are coupled
into a control or selection input of each MUX 480-482 for controlling what input signal each
Atty. Ref.: 2030P010NZD3
MUX 480-482 selects to output. The time signal selection logic 400 provides more flexibility in
the daughter card 222 so that it can receive internal time reference signals or external time
reference signals.
A plurality of time reference signals 440-443 may be coupled into the time signal
selection logic 400. An external time reference signal 440 and a first internal time reference
signal 441 are coupled into the input of the multiplexer 480 for selection. The external time
reference signal (EXT_CK) 440 is the time reference signal from the selected SFP time signal
adapter module. The first internal universal time reference signal (INT_CK) 441 is a backward
compatible time reference signal that may be selected so that the card 222 can be used as a
replacement card. A card specific internal time reference signal (CSP) 442 and a high resolution
internal time reference signal (HR_CK) 443 are coupled into the inputs of the multiplexer 481
for selection. The card specific internal time reference signal (CSP) 442 is a backward
compatible time reference signal that may be selected so that the card 222 can be used as a
replacement card. The high resolution internal time reference signal (HR_CK) 443 is a second
internal universal time reference signal with a higher resolution of time than that of the first
internal universal time reference signal (INT_CK) 441. The high resolution internal time
reference signal (HR_CK) 443 is a newer time reference signal that may be selected so that the
card is forward compatible and is used as a new card 222 in newer networking equipment.
The output 484,489 of the two to one multiplexer 480 is coupled into one or two
inputs of the output multiplexer 482. The output 494 of the two to one multiplexer 481 is
coupled into another input of the output multiplexer 482. The output multiplexer 482 may have
further inputs to receive other signals 486-488 when a time reference signal is unnecessary. In
one embodiment, the output multiplexer 482 is a six to one multiplexer. In another embodiment,
the output multiplexer 482 is a two to one multiplexer receiving the outputs 484 and 494 as two
inputs. An output 496 from the multiplexer 482 is the output from the time signal selection logic
400. In response to the select signal 492, the output 496 from the multiplexer 482 selectively
outputs the selected time reference signal that is used by the data packet processing circuit 352 of
Figure 3A to associate the date and time of the time stamp to data packets.
The output selection of the desired time reference signal is selected by the
configuration register 485. Time reference selection signals 490-492 generated by the
Atty. Ref.: 2030P010NZD3
configuration register 485 are respectively coupled into the select inputs (S) of the multiplexers
480-482. With the selection of the desired time reference signal, a software driver may write to
the configuration register 485 at runtime during initialization of the networking equipment to
generate the time reference selection signals 490-492. The various time reference signals that
are selectable may generate one or fewer pulses per second (PPS). In another case, the various
time reference signals that that are selectable may generate one or more pulses per second (PPS).
Small Form Pluggable Time Signal Adapter
Referring now to Figure 10A, a schematic diagram of an SFP time signal adapter
module 360 is shown. The SFP time signal adapter module 360 includes a differential receiver
transmitter 1021, a cable connector 458 (e.g., an RJ-45 female connector), and an SFP edge
connector 430 coupled together as shown. Conductive wire traces of a printed circuit board 1000
couple these elements together. The SFP time signal adapter module 360 further includes
inductive filters 1012A-1012D coupled between respective differential signal lines 1061A-
1061B,1062A-1062B and differential signal lines 1063A-1063B,1064A-1064B. The SFP time
signal adapter module 360 further includes protection circuits 1014A-1014D coupled to the
differential signal lines 1063A-1063B,1064A-1064B.
The differential receiver transmitter 421 includes a differential receiver 1002 and a
differential driver 1004. The differential receiver transmitter 421 further includes input resistors
1038A-1038B coupled to the differential signal input terminals of the differential receiver 1002.
The input resistors 1038A-1038B help establish the input impedance of the differential receiver
1002 to ground. The differential receiver transmitter 421 further includes a terminating resistor
1039 coupled in series with a transistor switch 1036. In response to the termination enable signal
TE 1053, the terminating resistor 1039 is selectively coupled between the differential inputs of
the differential receiver 1002 by a transistor switch 1036. The terminating resistor 1039, when
selected, establishes an input impedance between the differential signal input terminals of the
differential receiver 1002.
The SFP time signal adapter module 360 receives a differential time reference signal
from a cable 372 plugged into the cable connector 458. The differential time reference signal is
Atty. Ref.: 2030P010NZD3
generated by a time reference generator, such as the time reference generator 107 shown in
Figure 1B. In some embodiments, the differential time reference signal is a digital clock signal
that is generated in accordance with the IRIG-B time standard. In one embodiment, the digital
clock signal that is used for synchronization is generated at a rate of one pulse per second. The
rate may be greater than or less than one pulse per second in other embodiments.
The differential time reference signal is then processed through protection devices
1014C-1014D and filtered through filtering devices 1012C-1012D. If the voltage level of a
differential signal goes above the positive voltage supply of the SFP time signal adapter module,
then the zener diode 1015A in the input protection devices 1014A-1014D should clamp the
voltage to a diode turn on voltage above the positive voltage supply. If the voltage level of a
differential signal goes below the negative or lower voltage supply of the SFP time signal
adapter module, e.g., ground or zero volts, then the zener diode 1015B in the input protection
devices 1014A-1014D should clamp the voltage to a diode turn on voltage below the negative or
lower voltage supply.
The filtering devices 1012C-1012D are inductive filtering devices to filter out high
frequency noise and allow the clamped differential time reference signal to pass through to the
differential receiver 1002 and the input/terminating resistors.
With the differential time reference signal at its differential input signal lines
1062A-1062B, the differential receiver 1002 converts the differential signal into a single ended
time reference signal (TS OUT) at its output 1051. The single ended time reference signal is
coupled to a pad of the SFP edge connector 430.
The daughter card 222 manages the selection of the terminating resistor 1036 and
provides a termination enable control signal (TE). The termination enable control signal (TE) is
coupled to a pad of the SFP edge connector 430 becoming the TE control signal 1053 that
controls the transistor switch 1036.
The daughter card 222 may further send out a time signal output (TS OUT)
representative of the time reference signal. The TS OUT signal may be sent back to the time
reference generator 107. In this case, it may be used to acknowledge the receipt of the time
reference signal input from the time reference generator 107. In another case, a daughter card
Atty. Ref.: 2030P010NZD3
222 may further send out a time signal output (TS OUT) that is to be input into other daughter
cards 222 that are in close proximity, such as the same server. In this case, the TS OUT signal
allow daisy chaining of the time reference signal into other daughter cards (222) to preserve
ports and cabling that may otherwise be required of a switch 103 and a splitter 105.
The time signal output (TS OUT) is coupled into a pad of the SFP edge connector
430 becoming the TS OUT signal 1052. The TS OUT signal 1052 is a single ended non-
differential signal. It is desirable to convert it into a differential signal so that it can be sent over
the cable 372 and common noise can then be removed at the opposite end. The TS OUT signal
1052 is coupled into the single input (single ended input) of the differential driver 1004.
The differential driver 1004 receives the TS OUT signal 1052 and generates a
differential output signal (double ended signal) across its differential output signal lines
1061A,1061B (double ended output).
The differential TS OUT output signal from the differential driver 1004 is coupled
into the filtering devices 1012A-1012B. The filtering devices 1012A-1012B are inductive
filtering devices to filter out high frequency noise and allow the differential TS OUT signal to
pass. After passing through the filtering devices 1012A-1012B, the differential TS OUT signal
is clamped by the input protection devices 1014A-1014B. The output from the filtering devices
1012A-1012B are coupled to a terminal of the input protection devices 1014A-1014B. The
clamped differential TS OUT signal is then coupled to pins of the cable connector 458.
Accordingly, the SFP time signal adapter module 360 receives a differential serial
time reference input signal at the cable connector 458 and coverts it into a single ended serial
time reference input signal (TS IN) at the SFP edge connector 430 for coupling into the daughter
card 222. The SFP time signal adapter module 360 receives a single ended serial time output
signal (TS OUT) at the SFP edge connector 430 from the daughter card 222 and coverts it into a
double ended serial time output signal at the cable connector 458 for transmission over the cable
372.
A date and time stamp (collectively referred to as a timestamp) is encoded into the
single ended serial time reference input signal (TS IN). The single ended serial time reference
input signal (TS IN) at the SFP edge connector 430, a digital clock signal, is then deserialized
Atty. Ref.: 2030P010NZD3
and decoded by the data packet processor to add a date and time stamp to the data packets that
are received by the daughter card 222.
Referring now to Figure 10B, an alternate differential receiver transmitter 1021’ is
illustrated for an alternate time SFP time signal adapter module 360’. The alternate differential
receiver transmitter 1021’ is for receiving/transmitting modulated serial differential time signals
over the cable 372 of Figure 10A (the cable 372 is not shown in Figure 10B). The alternate
differential receiver transmitter 1021’ of Figure 10B includes the elements of the differential
receiver transmitter 1021 described herein in relation to Figure 10A. The alternate differential
receiver transmitter 1021’ of Figure 10B further includes a demodulating clock source 1022, a
modulating clock source 1034, and mixers 1020,1030.
The modulating clock source 1034 generates a local oscillating signal that is coupled
into the mixer 1030 to modulate the serial time output signal 1052. The modulated time output
signal is coupled into the differential driver 1004 to convert it from a single ended signal to a
differential signal. The demodulation clock source 1022 generates a local oscillating signal that
is coupled into the mixer 1020 to demodulate a modulated serial time input signal from the
differential receiver 1002 to generate the serial time input signal 1051. The frequency of the
demodulation clock 1022 should be the same frequency of the modulating clock at the opposite
end of the communication channel. The frequency of the modulation clock 1034 should be the
same frequency of the de-modulating clock at the opposite end of the communication channel.
Referring now to Figure 10C, a block diagram of an optical Ethernet SFP time
signal adapter 359 is shown. The optical Ethernet SFP time signal adapter 359 includes an
electro-optical signal adapter circuit 1023 for transmission and reception of optical time signals
over an optical cable. Exemplary embodiments of the electro-optical signal adapter module 1023
are shown by US Patent No. 6,941,077 issued to Aronson et al. on September 6, 2005; and US
Pat. No. 7,215,891 issued to Chiang et al. on May 8, 2007, both of which are incorporated herein
by reference. Exemplary embodiments of the mechanical aspects of the SFP module 359 are
shown and described herein, as well as by US Pat. No. 7,116,912 issued to Pang et al. on October
3, 2006 incorporated herein by reference.
With the optical Ethernet SFP time signal adapter module 359, a serial optical time
signal is transmitted over a fibre-over-Ethernet cable 160. The fibre-over-Ethernet cable 160
Atty. Ref.: 2030P010NZD3
may include two fibre optical cables for bidirectional communication of optical signals. The
cable 160 may have a pair of male optical connectors at each end. The male optical connector at
one end of the cable 160 are inserted into the female optical connectors 424 of the SFP time
signal adapter module 359. The optical input signal is coupled into the electro-optical signal
converter circuit 1023 to convert optical signals into electrical signals. The serial optical time
reference input signal is converted into a serial electrical time reference input signal. The serial
electrical time reference input signal is coupled to the SFP edge connector 430. With the SFP
time signal adapter module 359 plugged into the time port of the daughter card, the time
reference input signal is coupled to the data packet processor for deserialization and decoding to
extract the date and time information.
An electrical serial time output signal may be received by the module 359 from the
data packet processor of the daughter card. The electrical serial time output signal may be
coupled into the electro-optical signal converter circuit 1023 to covert a serial electrical input
signal into a serial optical output signal. The electro-optical signal converter circuit 1023
coverts the electrical serial time output signal into an optical serial time output signal. The
optical serial time output signal may then be coupled into an optical connector of the optical
connectors 424. With an optical cable 160 plugged into the optical connector 424, the optical
serial time output signal can be communicated back to the time reference generator over the
optical cable.
Referring now to Figure10D, a block diagram of an electrical Ethernet SFP time
signal adapter module 358 is shown. The electrical Ethernet SFP time signal adapter module 358
includes an Ethernet electrical signal adapter circuit 1025 mounted to a printed circuit board for
transmission and reception of time signal packets over a wire Ethernet cable. Exemplary
embodiments of the electrical signal adapter circuit 1025 are shown by US Patent No. 6,203,333
issued to Medina et al on March 20, 2001; US Pat. No. 8,419,444 issued to Kagan et al. on April
16, 2013, both of which are incorporated herein by reference. Another exemplary embodiment
of an electrical signal adapter circuit 1025 is a Vitesse Semiconductor Corporation media
converter having part number VSC8211.
A time signal packet is communicated over a copper Ethernet cable 160’ and
received at the cable connector 426 of the module 358. The time signal packet includes date and
Atty. Ref.: 2030P010NZD3
time information that is broadcast from the time reference generator. The time signal packet
may be depacketized by the Ethernet electrical signal adapter circuit 1025 with the date and time
information in a serial time reference input signal being serially communicated to the SFP edge
connector 430. The serial time reference input signal may then be communicated to the data
packet processing circuit through the SFP male edge connector 430 being coupled to a SFP
female edge connector on the daughter card.
One of a plurality of SFP time signal adapter modules is selected for coupling into
the time signal port of a network coprocessing daughter card. The selected SFP time signal
adapter may receive an optical time reference signal, an electrical time reference signal, or a
packetized time reference signal. The SFP time signal adapter module that may be selected may
be an electrical signal module such as a Fibre Channel over Ethernet SFP time signal adapter
module, a differential digital SFP time signal adapter module, a modulated SFP time signal
adapter module, or an Ethernet SFP time signal adapter module. The SFP time signal adapter
module that may be selected may be an opto-electrical signal module that may be a Fibre
Channel over Ethernet SFP time signal adapter module, or an Ethernet SFP time signal adapter
module.
Reference is now made to Figures 5-9 illustrating the electro-mechanical aspects of
the SFP time signal adapter modules.
In Figure 5, a block diagram of the electromechanical connections made between
the SFP female edge connector 556 and the SFP male connector 510 is illustrated. The SFP male
edge connector 510 provides the electrical connection of the pins of the SFP edge connector 430
for the SFP time signal adapter modules shown in Figures 10A-10D.
The edge connector 510 includes ten pads numbering one through ten on a bottom
portion 510B of the printed circuit board 500. The edge connector 510 further includes ten pads
numbering from eleven through twenty on a top portion 510T of the printed circuit board 1500.
The ten pads on the top portion 510T and the ten pads on bottom portion 510B are coupled to
traces 550 of the printed circuit board of the SFP time signal adapter module.
As shown in Figure 5, the daughter card 222 includes a time signal port including an
SFP electromagnetic interference (EMI) cage 512 and an SFP female electrical connector 556
Atty. Ref.: 2030P010NZD3
mounted to its printed circuit board. The SFP female electrical connector 556 is coupled to data
packet processing circuit 352 on the daughter card through printed circuit board traces
440,552,553.
The SFP electrical connector 556 includes a top connector portion 556T and a
bottom connector portion 556B. The top connector portion 556T has pins 12-20 to couple to
pads 11-20 of the top portion 510T of the SFP male edge connector 510 of the SFP time signal
adapter module. The bottom connector portion 556B has pins 1-10 to couple to pads 1-10 of the
bottom 510B of the SFP male edge connector 510.
Referring now to Figure 6, a side perspective view of an SFP time signal adapter
module 358-360, Ethernet cable 601, and daughter card 222 are shown ready to be plugged
together. The Ethernet cable 601 includes a male connector 603 to plug into the female
connector of the SFP time signal adapter module 358-360. The SFP time signal adapter module
358-360 includes the male SFP edge connector 510 to plug into the female SFP connector 556 of
the daughter card 222.
An opening of the EMI cage 512 aligns with an opening 604 in an adapter card
bracket 606 of the daughter card 222. A shell 610 of the SFP time signal adapter module 358-
360 includes protrusions 620T, 620R, 620L on top right and left sides that mate with the EMI
cage 512 to provide EMI shielding.
Within the EMI cage 512, the SFP edge connector 510 of the SFP time signal
adapter module 358-360 mates with the female SFP edge connector 556 that is mounted to the
printed circuit board 222. The female SFP edge connector 556 has pins 616 on either side to
couple to the traces of the printed circuit board 222 in order to make an electrical connection to
the data packet processing circuit 352 of Figures 3A and 3B.
Referring now to Figure 7, a side cross-sectional view of the, Ethernet cable 601, the
SFP time signal adapter module 358-360 assembled together into the time signal port 357E is
shown. The top protrusion 620 of the shell 610 is coupled to the EMI cage 512. The male SFP
edge connector 510 of the printed circuit board 500 is coupled into the female SFP edge
connector 556. The connector 603 of the Ethernet cable 601 is plugged into the female jack or
connector of the SFP time signal adapter module 358-360.
Atty. Ref.: 2030P010NZD3
Referring now to Figure 8, an exploded perspective view of an SFP time signal
adapter module 360 is shown. The exploded view shows the differential receiver transmitter
1021,1021’ mounted to the printed circuit board 500 between the male SFP edge connector 510
and the cable connector 458. The cable connector 458 includes pins 922 that are coupled to
traces of the printed circuit board 500. The printed circuit board 500 includes pinholes 912 into
which pins 922 of the connector 902 may be soldered. The pinholes 912 are coupled to printed
circuit board traces.
A connector housing 910 provides an opening 922’ through which a plug of an
Ethernet cable may be inserted and coupled to the cable connector 458.
The SFP time signal adapter module includes a catch (not shown) that can interface
with a latch of the EMI cage. The catch may be released by a release mechanism 814 that slides
within an opening 884 so that the SFP time signal adapter module 360 may be released from the
EMI cage 512.
The shell 610 of the SFP time signal adapter module 360 may be mounted to a base
800 around the connector housing 910. Left side openings 822L, 823L and right side openings
822R, 823R in the shell 610 mate with left side protrusions 881L, 882L and right side
protrusions 881R, 882R in the base 800 and connector housing 910.
Figure 9 illustrates a substantial assembled view of the SFP time signal adapter
module 360 without the shell 610 mounted to the base 800 and connector housing 910.
To assemble the components of the adapter 900 together, the base 800 includes a
pair of posts 840 that may be received within openings 842 of the printed circuit board 500.
After the posts 840 are inserted within the openings 842, the top of the posts may be deformed
such as by being mushroomed out so that it retains the printed circuit board 500 coupled to the
base.
Time Reference Signals
Referring now to Figure 11A, an IRIG-B time reference signal 1100 is shown in
waveform portions 1100A-1100B. The IRIG-B time reference signal consists of one hundred
bits. In one embodiment, the one hundred bits of the IRIG-B time reference signal are generated
Atty. Ref.: 2030P010NZD3
every second by the timing reference generator. Seventy-four bits of the IRIG-B time reference
signal contain various time, date, time changes and time quality information of the time signal.
The IRIG-B time reference signal is a decimal or binary signal comprising logical ones, zeros
and position identifier bits. The IRIG-B time reference signal provides a reliable means of
transmitting time to networking equipment.
Generally, there are three functional groups of bits in the IRIG-B time signal
including encoded date and time, control functions (CF) 1105, and straight binary seconds (SBS)
1109 of the day. Bits of the IRIG-B time signal may be encoded with a binary coded decimal
(BCD) to represent the time-of-year (in days 1117, hours 1115, minutes 1113, seconds 1111),
year 1119, straight binary seconds-of-day 1109, and control functions 1105. The binary coded
decimal (BCD) group of bits contains time information including seconds, minutes, hours and
days, recycling yearly. The BCD time-of-year code (BCDTOY) reads zero (0) hours, minutes,
seconds, and fraction of seconds at 2400 each day and reads day 001 at 2400 of day 365, or day
366 in a leap year. The BCD year code (BCDYEAR) counts year and cycles to the next year on
January 1st of each year and may count to year 2099.
An optional SBS time-of-day code 1109 comprises the total elapsed seconds,
recycling daily. SBS code reads zero (0) seconds at 2400 each day excluding leap second days
when a second may be added or subtracted.
The CF group of bits 1105 contains year, time quality, leap year, pending leap
seconds and parity. Other CF bits 1105 are reserved for user-defined purposes, depending on
application. For example, Daylight Saving Time (DST), and DST pending; local time offset;
time quality; and parity may be other CF bits. Position identifiers 1107A-1107K in the IRIG-B
time signal separate the various components of the IRIG-B time code.
Referring now to Figure 11B, the IRIG-B time reference signal 1100 can be
modulated (by a carrier signal or modulating signal) or unmodulated (no carrier signal) such as
with a DC Level Shifted (DCLS) or binary signal. In Figure 11B, a waveform 1110 illustrates an
exemplary unmodulated or DC level shifted IRIG-B time signal. Waveform 1112 illustrates an
exemplary amplitude modulated waveform that is responsive to the bits in the unmodulated
IRIG-B time signal. Waveform 1114 illustrates an exemplary modulation clock signal that may
Atty. Ref.: 2030P010NZD3
be used to Manchester encode the unmodulated IRIG-B time signal into a waveform 1116,
modified Manchester encoded time signal.
The IRIG-B time reference signal can be transmitted over optical cables, shielded
twisted pair wire cables, or coaxial cables. Alternatively, a time reference signal may be
packetized into an Ethernet packet with the Ethernet packet being transmitted over cables to the
networking equipment in the local area network.
Referring now to Figure 12, a frame 1200 for an Ethernet time packet 1202 is
shown. The frame 1200 includes a transport protocol 1201, timing element, and a precision time
protocol (PTP) 1203, that time stamps or associates time with the Ethernet packet 1202. The
association of the precision time protocol with the Ethernet packet provides accurate
synchronization between resources in the communication of the data contained within the
Ethernet time packet.
The Ethernet time packet 1202 further includes a header field and a data field. The
header field of the Ethernet time packet 1202 includes a destination or receiver media access
control (MAC) address, a source or sender MAC address, and a field of a number of bytes of
optional header information.
The data field of the Ethernet time packet 1202 includes an IP packet 1204, which
includes a header field and a data field. The header field of the IP packet 1204 includes a version
field, a header length field, a type of service (ToS) field, a total length field, a packet identifier, a
time to live (TTL) field, a protocol field 1208, a header checksum, a source IP address 1210, and
a destination IP address 1212.
The data field of the IP packet 1204 may include a transmission control protocol
(TCP) packet, a user datagram protocol (UDP) packet, or a stream control transmission protocol
(SCTP) packet. Figure 12 illustrates a transmission control protocol (TCP) packet 1206
including a header field and a data field. The header field of the TCP packet 1206 includes a
source port number 1214, a destination port number 1216, a send number, an acknowledgement
number, one or more flags, and a checksum.
Atty. Ref.: 2030P010NZD3
In this specification where reference has been made to patent specifications, other
external documents, or other sources of information, this is generally for the purpose of
providing a context for discussing the features of the invention. Unless specifically stated
otherwise, reference to such external documents is not to be construed as an admission that such
documents, or such sources of information, in any jurisdiction, are prior art, or form part of the
common general knowledge in the art.
The term “comprising” as used in this specification and claims means “consisting at
least in part of”. When interpreting statements in this specification and claims which include the
term “comprising”, other features besides the features prefaced by this term in each statement
can also be present. Related terms such as “comprise” and “comprised” are to be interpreted in
similar manner.
The embodiments are thus described. While this specification and the drawing
figures include many specific aspects, these should not be construed as limitations on the scope
of the disclosure or of what may be claimed, but rather as descriptions of aspects specific to
particular implementations. Certain aspects that are described in this specification in the context
of separate implementations may also be implemented in combination in a single
implementation. Conversely, various aspects that are described in the context of a single
implementation may also be implemented in multiple implementations, separately or in sub-
combination. Moreover, although aspects may be described above as acting in certain
combinations and even initially claimed as such, one or more aspects from a claimed
combination may in some cases be excised from the combination, and the claimed combination
may be directed to a sub-combination or variations of a sub-combination. Moreover, various
modifications to the aspects and embodiments described herein may be determined by those of
ordinarily skilled in the art after reading this disclosure. Accordingly, the claims should not be
construed as limited by such described embodiments, but rather construed according to the claim
limitations that follow below.
Atty. Ref.: 2030P010NZD3
Claims (14)
1. A system comprising: a router to receive and transmit data packets; a switch coupled to the router; a time reference generator coupled to the router; a plurality of coprocessing cards coupled in communication with the switch and the time reference generator, each coprocessing card includes a plurality of multiplexers coupled in communication together, wherein the plurality of multiplexers of each coprocessing card to receive a plurality of differing time reference signals and select one as a selected time reference signal of the coprocessing card; a plurality of small form pluggable time modules coupled to the plurality of coprocessing cards; wherein the switch receives data signal packets and routes the data signal packets to the plurality of coprocessing cards for processing; and wherein the time reference generator generates an external time reference signal as one of the plurality of differing time reference signals, the external time reference signal is communicated to each of the plurality of small form pluggable time modules capable of being selected by the plurality of multiplexers as the selected time reference signal of the coprocessing card.
2. The system of claim 1, wherein the switch routes copies of data signal packets in a load balanced manner to each of the Atty. Ref.: 2030P010NZD3 plurality of coprocessing cards.
3. The system of claim 1, wherein the plurality of small form pluggable time modules are further coupled to the switch to receive time signal packets from the time reference generator.
4. The system of claim 3, wherein each of the plurality of small form pluggable time modules are electro-optical small form pluggable time modules, and the system further comprises: a plurality of optical cables coupled to and between the switch and the plurality of electro-optical small form pluggable time modules.
5. The system of claim 3, wherein each of the plurality of small form pluggable time modules are electrical small form pluggable time modules, and the system further comprises: a plurality of wired Ethernet cables coupled to and between the switch and the plurality of electrical small form pluggable time modules.
6. The system of claim 1, further comprising: a splitter coupled to the time reference generator to split an external time reference signal from the time reference generator into a plurality of external time reference signals; wherein the plurality of small form pluggable time modules are respectively coupled to the splitter to receive one of the plurality of external time reference signals. Atty. Ref.: 2030P010NZD3
7. The system of claim 6, wherein each of the plurality of small form pluggable time modules are electrical small form pluggable time modules, and the system further comprises: a plurality of wired Ethernet cables coupled to and between the switch and the plurality of electrical small form pluggable time modules.
8. The system of claim 6, wherein each of the plurality of small form pluggable time modules are optical small form pluggable time modules, and the system further comprises: a plurality of optical cables coupled to and between the switch and the plurality of optical small form pluggable time modules.
9. The system of claim 1, wherein an internal generated clock generated by the coprocessing card is another one of the plurality of time reference signals that can be selected by the plurality of multiplexers as the selected time reference signal of the coprocessing card.
10. The system of claim 1, wherein a card specific internal time reference signal generated by the coprocessing card is another one of the plurality of time reference signals that can be selected by the plurality of multiplexers as the selected time reference signal of the coprocessing card.
11. The system of claim 1, wherein an internal universal time reference signal generated by the coprocessing card is another one of the plurality of time reference signals that can be selected by the plurality of multiplexers as the selected time reference signal of the coprocessing card.
12. The system of claim 1, wherein a high resolution internal time reference signal generated Atty. Ref.: 2030P010NZD3 by the coprocessing card is another one of the plurality of time reference signals that can be selected by the plurality of multiplexers as the selected time reference signal of the coprocessing card.
13. The system of claim 1, wherein the selected time reference signal is used by the coprocessing card to time stamp data packets with a time and date.
14. The system of claim 1 substantially as herein described with reference to the figures and/or examples.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201462048098P | 2014-09-09 | 2014-09-09 | |
US62/048,098 | 2014-09-09 | ||
NZ735955A NZ735955A (en) | 2014-09-09 | 2014-09-11 | Systems for selecting a time reference |
Publications (2)
Publication Number | Publication Date |
---|---|
NZ754292A NZ754292A (en) | 2020-12-18 |
NZ754292B2 true NZ754292B2 (en) | 2021-03-19 |
Family
ID=
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10992403B2 (en) | Pluggable time signal adapter modules for selecting a time reference | |
US8165471B2 (en) | Form factor adapter module | |
CN103329365B (en) | There are 180 degree and connect connector accessory freely | |
US10419323B2 (en) | Modulation analyzer module | |
US8340123B2 (en) | Multi-channel transceiver module card | |
US9584137B2 (en) | Transceiver unit | |
US6600727B1 (en) | Distributed network repeater system | |
US20210328900A1 (en) | Time-Synchronization Testing in a Network Element | |
CN209489030U (en) | Master control cabinet and power electronic control system | |
US20060291857A1 (en) | Method and apparatus for testing optical network equipment | |
CN215072446U (en) | EtherCAT slave station module | |
CN109818677A (en) | Optical module and optical network apparatus | |
US20170371823A1 (en) | Bidirectional lane routing | |
US8611830B2 (en) | Transceiver port apparatus and method | |
NZ754292B2 (en) | Systems for selecting a time reference | |
US10566714B2 (en) | High-density small form-factor pluggable module, housing, and system | |
US20040088133A1 (en) | Xaui extender card | |
US10491722B2 (en) | System and a method for a line encoded data stream | |
US9960811B1 (en) | DC bias signals isolatable from transmission protocols | |
US7184395B2 (en) | Providing reconditioned signals at a plurality of ports | |
WO2016172765A1 (en) | A system for multiplexing a plurality of payloads and a method for multiplexing a plurality of payloads | |
EP1453346A1 (en) | Configurable electrical transceiver in a small form factor pluggable module realising coded interfaces | |
CN220795836U (en) | Interface adapter plate and server | |
Cachemiche et al. | Recent developments for the upgrade of the LHCb readout system | |
CN110275848B (en) | Adapter card |