Beta Draft Confidential
8-461/19/05 ATM Services Configuration Guide for CBX 3500, CBX 500, GX 550, and B-STDX 9000
Configuring ATM Over MPLS Trunks
Configuring the ATMoMPLS Trunk
Hold Down Time Accept the default value 0 (zero), or enter a value between 0 and 
65535 (seconds).
Hold down time allows you to configure the time delay (in 
seconds) before link state advertisements (LSAs) are generated 
when a trunk recovery takes effect on the network. The time 
delay is not used when a trunk is brought up for the first time, 
when a trunk’s Open Shortest Path First (OSPF) area ID 
changes, and when a trunk goes down. This setting can reduce 
the number of LSAs caused by rapid changes in trunk status.
Traffic Allowed Select one of the following options from the pull-down list to 
designate the type of traffic allowed on this trunk:
• All – Trunk can carry SVC, PVC, and network management 
traffic.
• Management Only – Trunk can carry only network 
management traffic, such as SNMP communication between 
a switch and the NMS.
• Management & User Data – Trunk can carry PVCs and 
network management traffic. This trunk option does not 
support SVC addressing information. If this is the only trunk 
between two nodes and you configure this option for it, then 
you effectively prevent SVC traffic from traversing this 
trunk.
Layer 2 VPN Name Select a Layer2 Virtual Private Network (VPN) name. The 
default is Public. To select a different Layer2 VPN name, clear 
the Default check box and choose the Select Layer2 VPN button. 
For more information about Layer2 VPNs, see Chapter 13, 
“Configuring Layer 2 VPNs.”
Defined Bandwidth 
(Kbps)
Displays the amount of defined bandwidth in Kbps.
Virtual Bandwidth 
(Kbps)
Displays the amount of virtual bandwidth in Kbps.
The value .95 is used because .05% of the bandwidth is reserved 
for network management, routing updates, and other 
management traffic.
Area ID Areas are collections of networks, hosts, and routers used for IP 
routing. The area ID identifies the area. The range of available 
values is from 0.0.0.0 to 255.255. 255.255. Area 0.0.0.0 is the 
network backbone area. Area 0.0.0.1 is Area 1. For a detailed 
description of OSPF areas, and how to use IP to configure 
multiple OSPF areas, see the IP Services Configuration Guide 
for CBX 3500, CBX 500, and B-STDX 9000.
Table 8-13. Add Trunk: Administrative Tab (Continued)
Field Action/Description