3Com 11.1 - page 14

New Features 15

OSPF Not-So-Stubby-Area (NSSA)

For inter-area routing, the Area Border Router (the only attachment to the

backbone for leaf sites) advertised a default route. However, when fairly complex

leaf sites are connected to the backbone via a Stub Area, inter-area routing into

and out of the leaf site is not optimal with only a default route. RFC 1587

proposes a new kind of area known as NSSA (Not-So-Stubby-Area) to address this

problem. NETBuilder software version 11.1 implements this new functionality.

Frame Relay PVC Q.933 Support

ITU Q.933 Annex A Frame Relay PVC signaling is the latest deﬁned by ITU that

supports asynchronous bidirectional PVC control procedure. With the

implementation of this new signaling standard, you can signal the network for the

activation or deactivation of individual PVCs. Additionally, you can query the

network regarding the operational status of the PVC. Q.933 Annex A is a super set

of the existing LMI supported in the NETBuilder bridge/router platforms.

Data Over Voice (B-Channel ISDN Speciﬁcation)

This feature enables the bridge/router to initiate an ISDN 56 Kbps data call over

the ISDN voice bearer channel. Connection at the remote end must be able to

accept the incoming call and supply the proper signal to disable echo suppressors.

This feature is sometimes referred to as Switched 56 Permissive mode or TollSaver.

See “Placing a Data Over Voice Call” on page 17 for brief description of how to

use this feature.

System Features This release implements the following general system features.

Boundary Router Remote LAN Detection

Central site support of Boundary Routing Architecture has been enhanced to

detect the LAN media type of the connected remote boundary routers.

MBRI Digi64S2 Support

This release implements the German dual point-to-point leased line switch

speciﬁcation Digi64S2, on the NETBuilder II bridge/router 8-port BRI Module.

Digi64S2 was implemented in prior releases of the OfﬁceConnect NETBuilder

bridge/router and SuperStack II NETBuilder SI bridge/router product lines

containing ISDN interfaces. This feature allows each ISDN port on the NETBuilder

to be connected to either the same or different remote node locations as a leased

line. See “Digi64S2” on page 18 for a brief description of how to use this feature.

Legacy/ATM Features This software release implements the following legacy and ATM features.

Multiprotocol over ATM (MPOA)

An ATM network can be divided into multiple logical internet subnets (LISs) or

emulated LANs (ELANs), which requires that all ELAN trafﬁc go through routers

that are connected to the ELANs. The NETBuilder II bridge/router in a LAN

emulation topology is used to perform the routing between the ELANs in which

the NETBuilder II bridge/router has joined. On a large site, it is quite likely that

there would be two or more routers on the data path between the edge devices. If