- Enterasys Security Router User's Guide
Interconnecting via Frame Relay Network
9-10 Configuring Frame Relay
Interconnecting via Frame Relay Network
The following typical application uses FR to link remote branches to the corporate network at the
central sites via a FR network, as shown in Figure 9-3.
Figure 9-3 Branch/Central Frame Relay Topology
New York
Minneapolis
Frame Relay
Houston
Chicago
Memphis
Frame Relay switch combines DLCIs from various
remote branch sites at 56 kbps into a single high
speed Frame Relay T1 interface with a large
number of DLCIs at the central sites.
Central Sites
Branch Sites
• High speed FR link (clear channel T1/
E1 links, may be channelized or
fractional T3)
• Many DLCIs per link
• May use sub-interfaces to connect to
multiple subnets, each spanning
multiple remote sites
• Link to many remote sites, may use FR
QoS templates to address different
remote sites
• Medium speed FR links (32 - 128 kbps)
• 1-4 DLCIs linking one or more central
sites on different subnets
• All DLCIs share characteristics (CIR,
Bc, Be)
•IP traffic requires traffic prioritization,
bandwidth allocation
Boston
Network
Tor on t o