2-6 Riverstone Networks RS 8000/8600 Switch Router Getting Started Guide
Software Overview
Introduction
2.3.4
Layer-4 Switching
In addition to layer-2 bridging and layer-3 routing, the RS performs layer-4 switching. layer-4 switching is based on
applications and flows.
Layer-4 Applications
– The RS understands the application for which an IP or IPX packet contains data and therefore
enables you to manage and control traffic on an application basis. For IP traffic, the RS looks at the packet’s TCP or
UDP port number to determine the application. For IPX packets, the RS looks at the destination socket to determine
the application.
Layer-4 Flows
– The RS can store layer-4 flows on each line card. A layer-4 flow consists of the source and destination
addresses in the IP or IPX packet combined with the TCP or UDP source and destination port number (for IP) or the
source and destination socket (for IPX). You can therefore manage and control individual flows between hosts on an
individual application basis.
A single host can have many individual layer-4 entries in the RS. For example, an IP host might have separate layer-4
application entries for email, FTP, HTTP, and so on, or separate layer-4 flow entries for specific email destinations and
for specific FTP and Web connections.
2.3.5
MPLS Support
Multi Protocol Label Switching (MPLS) is supported on the RS 8000/8600 through software and through hardware on
the G8M-GBCMM-02 Gigabit Ethernet line card, G8M-PO3MM-02 2-port OC-3 line card, and G8M-PO3MM-02
2-port OC-12 line card. The following MPLS capabilities are supported on the RS 8000/8600:
•
Complete Label Edge Router (LER) and Label Switching Router (LSR) functionality with no impact
on performance
•
Label generation and swapping, along with push and pop operations for supporting multiple levels
of label stacking
•
Tunneling of layer-2 Ethernet over MPLS (for Gigabit Ethernet card)
•
Tunneling of layer-2 bridged PPP traffic over MPLS (for OC-3/OC-12 modules)
•
Support for thousands of label switched paths
•
Support for static and dynamic creation of LSPs
•
Label Distribution Protocol (LDP) and Resource Reservation Protocol with Traffic Engineering
(RSVP-TE) for label distribution and dynamic Label Switched Path (LSP) creation with support for
LDP over LDP and LDP over RSVP, allowing different tunneling schemes
•
Standby LSPs and fail over
•
Traffic engineering extensions to OSPF and IS-IS, along with Constrained Shortest Path First
(CSPF)
•
MPLS VPNs over BGP
2.3.6
Security
The bridging, routing, and application (layer-2, layer-3, and layer-4) support described in previous sections enables
you to implement security strategies that meet specific needs. For layer-2, a wide range of bridging filters are available.
Additionally, all layers can be protected using Access Control Lists (ACLs) filters. You can implement the following
types of filters and ACLs to secure traffic on the RS:
•
Layer-2 source filters (block bridge traffic based on source MAC address)