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Configuring ATM Over MPLS Gateway Solution on CBX 3500
Configuring a Layer 2 Tunnel Over MPLS Core Network
ATM Services Configuration Guide for CBX 3500, CBX 500, GX 550, and B-STDX 9000 1/19/059-41
Router Priority 
(0-255)
Enter a value between 0 (zero) and 255 (the default value is 1). 
This number identifies the priority of the router associated with 
this logical port and is used to elect the Designated Routers and 
Backup Designated Routers. The router with the highest priority 
is considered the Designated Router. A value of 0 (zero) indicates 
the router is not eligible to be the designated or Backup 
Designated Router. If all routers have the same priority, the router 
ID is used to determine the Designated Router.
TOS 0 Metric 
(1-65535)
Enter a value between 0 and 65535 (the default value is 1). This 
value specifies the type of service cost. The lowest TOS 0 has the 
highest priority for routing. 
Authentication 
Type
Specify the type of authentication that OSPF uses as a security 
measure to ensure that this logical port and router exchange 
information with correct neighbors. Options include:
None – (default) Specifies that no authentication is performed. 
Simple Password – Specifies a simple password authentication 
method that includes a password in all OSPF messages on an 
interface-by-interface basis. When a router receives a message on 
an interface that uses simple password authentication, the router 
checks the incoming OSPF message to see if the password is 
included in the message. If the password is correct, the message 
is processed normally. If the password is not part of the incoming 
message, the message is ignored and dropped. 
MD5 – Use MD5 authentication to verify a key that is appended 
to the end of an IP OSPF protocol packet. For more information 
on how MD5 authentication works, see RFC 1321 (The MD5 
Message-Digest Algorithm). In addition to RFC 1321, RFC 2178 
(OSPF Version 2) provides information on how MD5 
authentication is used with IP OSPF.
Authentication 
Key
An authentication password if SIMPLE is specified as the 
authentication type. This value is not required if NONE is 
selected as the authentication type. 
OSPF TE Metric 
(1-max Metric)
Enter a value between 1 (default) and 65535. The OSPF traffic 
engineering metric specifies the OSPF link metric for traffic 
engineering purposes. This metric may be different than the 
standard OSPF link metric. Typically, this metric is assigned by a 
network administrator, and used primarily by the 
constraint-based SPF calculation for MPLS tunnel setup. 
Table 9-16. Add OSPF IP Interface Fields (Continued)
Field Action/Description