Gre And Ipip Tunneling; Pppoe Client - Nortel Secure 4134 Configuration

GRE and IPIP tunneling

A tunnel is a logical interface that provides a framework for encapsulating
passenger packets inside a transport protocol. GRE and IPIP are
standards-based (RFC2784) (RFC1853) tunneling protocols that can
encapsulate packets inside an IP tunnel, creating a virtual point-to-point link
between routers at remote points over an IP network.
The advantage of using tunnels is that, while IPsec VPNs only function with
IP unicast frames, GRE and IPIP are capable of handling the transportation
of IP multicast traffic between two sites that only have IP unicast connectivity.
If encryption is required for a tunnel, you can enable IPsec transport mode
over GRE/IPIP tunneling.
The SR4134 also supports a tunneling feature set for transitioning to IPv6,
including IPv6 over manually-configured IPv4 tunnels, IPv6 over IPv4 GRE
tunnels, and automatic 6to4 tunnels. These tunneling features provide a
basic way for IPv6 hosts or islands to reach other IPv6 entities using IPv4
routing domains as the transport layer.
Multicast routing and unicast routing are supported on all tunnels, except
automatic 6to4 tunnels.
For information on IPsec VPN fundamentals, see
fundamentals" (page
IPIP tunnel configuration" (page

PPPoE client

PPPoE (RFC 2516) is a commonly used application in the deployment of
DSL One of the main advantages of PPPoE is that it offers authentication
based on Password Authentication Protocol (PAP) or Challenge Handshake
Authentication Protocol (CHAP).
With the SR4134, the PPPoE client must be deployed with a DSL modem
providing a connection to a PPPoE server for access to Internet resources.
The main purpose of PPPoE is to serve as a backup and fail-over solution.
When the primary connectivity goes down, traffic can switch over to a
backup interface, in this case the virtual PPPoE interface. In this scenario,
a PPPoE client session is established with a PPPoE server and traffic is
routed through this path until the primary connectivity is restored.
For information on PPPoE client fundamentals, see
fundamentals" (page
configuration" (page
Copyright © 2007, Nortel Networks
.
65). For configuration information, see
69). For configuration information, see
191).
Nortel Secure Router 4134
Security — Configuration and Management
NN47263-600 01.02 Standard
10.0 3 August 2007
"GRE and IPIP tunneling
181).
"PPPoE client
Features 15
"GRE and
"PPPoE client