Cisco Systems 1600R, 1400 series manual Area sham-link cost, Command Modes Command History

Page 13

OSPF Sham-Link Support for MPLS VPN

area sham-link cost

area sham-link cost

To configure a sham-link interface on a provider edge (PE) router in a Multiprotocol Label Switching (MPLS) Virtual Private Network (VPN) backbone, use the area sham-link cost command in global configuration mode. To remove the sham-link, use the no form of this command.

area area-id sham-linksource-address destination-address cost number

no area area-id sham-linksource-address destination-address cost number

Syntax Description

 

area-id

ID number of the Open Shortest Path First (OSPF) area assigned to the

 

 

 

sham-link. Valid values: numeric value or valid IP address. There is no

 

 

 

default.

 

 

 

 

 

 

source-address

IP address of the source PE router in the format: ip-address[mask].

 

 

 

 

 

 

destination-address

IP address of the destination PE route in the format: ip-address[mask].

 

 

 

 

 

 

number

OSPF cost to send IP packets over the sham-link interface.

 

 

 

Valid values are from 1 to 65535.

 

 

 

 

 

 

 

Defaults

 

No default behavior or values.

Command Modes

Command History

Global configuration

ReleaseModification

12.2(8)T

This command was introduced.

 

 

Usage Guidelines In the MPLS VPN environment, several VPN client sites can be connected in the same OSPF area. If these sites are connected over a backdoor link in addition to the VPN backbone, all traffic passes over the backdoor link instead of over the VPN backbone. OSPF always selects intra-area routes over interarea (external) routes.

To correct this default OSPF behavior in an MPLS VPN, use the area sham-link cost command to configure a sham-link between two PEs to connect the sites through the MPLS VPN backbone. A sham-link represents an intra-area (unnumbered point-to-point) connection between PEs. All other routers in the area see the sham-link and use it to calculate intra-area shortest path first (SPF) routes to the remote site.

Configure the source and destination addresses of the sham-link as a host route mask (255.255.255.255) on the PE routers that serve as the endpoints of the sham-link. The source and destination IP addresses must belong to the VRF and be advertised by Border Gateway Protocol (BGP) to remote PE routers. The sham-link endpoint addresses should not be advertised by OSPF.

Cisco IOS Release 12.2(8)T

13

Image 13
Contents Using Ospf in PE-CE Router Connections Feature OverviewFeature History ReleaseModification Using a Sham-Link to Correct Ospf Backdoor Routing From 0.0.0.0 PE-1#show ip bgp vpnv4 allPE-1#show ip route vrf ospf Sham-Link Configuration Example Vpnv4 all tag begin Sham-Link ExampleBenefits Flexible Routing in an Mpls VPN ConfigurationClient Site Connection Across the Mpls VPN Backbone Supported Platforms Related Features and TechnologiesRestrictions Related DocumentsDetermining Platform Support Through Cisco Feature Navigator Supported Standards, MIBs, and RFCs Configuration TasksPrerequisites Creating a Sham-LinkVerifying Sham-Link Creation Command PurposeCommand Reference Configuration ExamplesMonitoring and Maintaining a Sham-Link Show ip ospf sham-linksArea sham-link cost Command Modes Command History120 ExamplesShow ip ospf sham-links DefaultsUsage Guidelines Router1# show ip ospf sham-linksGlossary
Related manuals
Manual 52 pages 58.61 Kb Manual 13 pages 25.35 Kb

1600R, 1600, 1400 series specifications

Cisco Systems 1600 series routers are well-regarded in the networking industry for their reliability, versatility, and performance. Designed to meet the needs of small to medium-sized businesses, the Cisco 1600 series is primarily oriented towards providing robust connectivity for branch offices and remote sites.

One of the most significant features of the Cisco 1600 series is its modular architecture. This allows users to customize their routers with various interface cards, enabling support for different types of WAN technologies, including serial, ISDN, and Frame Relay. The modular design not only enhances flexibility but also extends the lifespan of the equipment, as businesses can upgrade their capacity and functionalities according to evolving demands.

Another key characteristic of the Cisco 1600 routers is their advanced routing capabilities. These devices support a wide range of routing protocols, including RIP, OSPF, EIGRP, and BGP. This versatility ensures seamless integration into existing network infrastructures, facilitating the scalability and adaptability that modern networks require.

Security is also a crucial aspect of the Cisco 1600 series. Incorporating features such as access control lists (ACLs) and support for Virtual Private Networks (VPNs), these routers help businesses safeguard their sensitive data during transmission. Enhanced security features allow companies to implement secure remote access for employees, thereby maintaining productivity without compromising safety.

In addition to routing and security, the Cisco 1600 series boasts Quality of Service (QoS) capabilities. This technology enables better management of network traffic, ensuring that critical applications receive the bandwidth they need for optimal performance. By prioritizing important data flows, businesses can enhance user experience and minimize disruptions across their network.

The Cisco 1600 series routers are also equipped with user-friendly interfaces and management tools. Cisco's IOS software platform provides a command-line interface (CLI) and web-based graphical interface for straightforward configuration and monitoring. This simplifies network management tasks and reduces the learning curve for IT personnel.

In summary, the Cisco Systems 1600 series routers offer a significant combination of modularity, robust routing protocols, enhanced security measures, Quality of Service features, and user-friendly management options. These characteristics make them an excellent choice for small to medium-sized enterprises looking to establish a reliable and secure networking infrastructure. With the continued evolution of networking technologies, the Cisco 1600 series stands as a dependable solution for businesses navigating an increasingly complex digital landscape.