Here, IPv6 traffic is transported between CE1 and CE2 routers over Any Transport over MPLS (AToM) Layer-2 circuit. PE routers are not required to be dual-stack routers. A Layer-2 circuit is established between PE1 and PE3 routers. CE1 & PE1 Configuration CE1 router: interface Serial 0/0  encapsulation ppp ipv6 address 2001:1::1/124  ipv6 ospf 1 area 0 ! interface Loopback 0  ipv6 address ABCD::1/128  ip ...

An IPv6 VPN is connected over an IPv6 interface or sub-interface to the Service Provider (SP) backbone via a PE router. The site can be both IPv4 and IPv6 capable. Each IPv6 VPN has its own address space which means a given address denotes different systems in different VPNs. This is achieved via a new address family- VPN-IPv6 or VPNv6 address-family which prepends a Route Distinguisher (RD) to the IP addre ...

Approach 3: In the approach, IPv6 prefixes are not maintained or distributed by ASBR routers. The ASBR routers are not dual-stack capable. The inter-ASBR link is IPv4 and MPLS enabled. An ASBR needs to maintain labeled IPv4 /32 routes to the 6PE routers within the AS. It uses eBGP to distribute these routes to other ASes. ASBRs also uses eBGP to pass along the labeled IPv4 /32 routes. This results in creati ...

RFC 4798 describes three approaches to provide communication between two IPv6 islands connected to two different BGP Autonomous Systems (AS). These approaches are- eBGP redistribution of IPv6 routes from AS to neighboring AS eBGP redistribution of labeled IPv6 routes from AS to neighboring AS Multihop eBGP redistribution of labeled IPv6 routes between source and destination ASes, with eBGP redistribution of ...

Cisco 6PE solution enables IPv6 domains to communicate with each other over MPLS IPv4 core network. MP-BGP in the IPv4 network is used to exchange IPv6 reachability information along with a label for each IPv6 prefix announced. 6PE routers are dual-stack routers i.e. running IPv6 with the customers and IPv4 in the core. The MP-BGP AFI used is IPv6 (value 2). This way the 6PE routers convey their IPv4 addres ...

Theory: RFC 4891 discusses about IPSec with IPv6-in-IPv4 tunnels. It points out two different types of threats with IPv6-in-IPv4 tunnels which mandates the use of IPSec. The two types of threats are- 1) The IPv4 source address of the encapsulating (outer) packet can be spoofed 2) The IPv6 source address of the encapsulated (inner) packet can be spoofed. RFC 4891 discusses two ways to use IPSec- in transport ...

  Here, the following steps are taken on the host (Windows XP) to make it ISATAP-capable- IPv6 is disabled by default in Windows XP. To enable, use ipv6 install command from the command-prompt. The host needs to resolve the IPv4 address for the name "ISATAP". This can be done in one of following ways- Manually provide the IPv4 address of the ISATAP Router using netsh interface ipv6 isatap set router 19 ...

Automatic 6to4 tunnel is a method to connect IPv6 domain through IPv4 cloud. It assigns a unique IPv6 prefix to any site that currently has atleast one globally unique IPv6 address. It provides mechanism for transmitting IPv6 packets using such a prefix over global IPv4 network. The IANA has assigned one 13-bit Top Level Aggregator (TLA) under IPv6 Format Prefix (FP) 001 for 6to4 scheme. Its numeric value i ...

Dual Stack is a way to implement IPv6 and still remain compatible with IPv4. A node that runs both IPv6 and IPv6 protocol stacks is called an IPv6/IPv6 node. An IPv6/IPv4 node communicates using IPv6 packets with IPv6 nodes and using IPv4 packets with IPv4 nodes. Consider the following- Two IPv6/IPv4 nodes, R5 and R6, are connected to each other via a Fastethernet interface. The Fastethernet interface is co ...

   Hub router- ipv6 unicast-routing ipv6 cef ! interface serial 1/0 no ip address encapsulation frame-relay ! interface serial 1/0.1 multipoint ipv6 address FE80::1 link-local ipv6 address 2001::1/124 frame-relay interface-dlci 102 frame-relay interface-dlci 103 frame-relay map ipv6 2001::2 102 broadcast frame-relay map ipv6 FE80::2 102 frame-relay map ipv6 2001::3 103 broadcast frame-relay map ipv6 FE ...