Installation guide

3-37
Cisco IGX 8400 Series Installation Guide, Release 9.3.3 and Later Releases
OL-1165-06
Chapter 3 Installing the IGX
Making Frame Relay Connections
Maximum Connections per Port with Signaling Protocols
For any Frame Relay card set that has a maximum frame length of 4510 bytes, the type of signaling
protocol you can (optionally) specify with the cnffrport command results in a limit on the number of
connections per physical or logical port. The maximum number of connections per port for each protocol
is:
• For Annex A: 899
• For Annex D: 899
• For StrataLMI: 562
Neither the addcon
nor the cnffrport command prevents you from adding more than the maximum
number of connections on a port. (You might, for example, use the cnffrport command to specify an
LMI when too many connections for that particular LMI already exist.) If the number of connections is
exceeded for a particular LMI, the LMI does not work on the port, the full status messages that result
are discarded, and LMI timeouts occur on the port. A port failure results and subsequently leads to a-bit
failures in other segments of the connection path.
Setting Up Frame Relay on a UFM
Channelized and unchannelized versions of the UFM card sets exist. The channelized front cards,
UFM-4C and UFM-8C, operate with T1 and E1 interfaces, and the unchannelized front card, UFM-U,
operates with V.35, X.21, and HSSI interfaces.
The back cards have the following terminations:
• The UFI-8T1-DB-15 has 8, female, subminiature DB-15s.
• The UFI-8E1-DB-15 has 8, female, subminiature DB-15s.
• The UFI-8E1-BNC has 16 BNC connectors, 1 for each direction.
• The UFI-12V.35 has 6 low-force helix (LFH) connectors with 2 ports per connector.
• The UFI-12X.21 has 6 low-force helix (LFH) connectors with 2 ports per connector.
• The UFI-4HSSI has 4 connectors.
If the installation includes Y-cable redundancy, first read the “Y-Cable Redundancy on the UFMs”
section on page 3-37.
Y-Cable Redundancy on the UFMs
Redundancy for a Frame Relay port is possible with a second card set and the appropriate Y-cable. The
card redundancy kit for UFM contains a second UFM/UFI card set and Y-cables to interconnect the ports
on the two back cards. The “Setting Up Frame Relay Ports and Connections (UFM)” section on
page 3-39 includes the step for configuring Y-cable redundancy.
Refer to the cabling description in the UFM-U section of the Cisco IGX 8400 Series Provisioning Guide
for descriptions and part numbers of all cables for unchannelized UFMs.
Figure 3-15 shows the Y-cable arrangement for standard cables that support one or two ports. The
diagram for single-port cables applies to all back cards. The dual-port cables connect to only a V.35 or
X.21 UFI. The Y-cable connects to the back card, and the standard cable runs between the access device
or CPE and the base of the Y.