VPN Routing and Forwarding Tables
The overlapping addresses, usually resulting from usage of private IP addresses in customer networks, are one of the major obstacles to successful deployment of peer-to-peer VPN implementations. The MPLS/VPN technology provides an elegant solution to the dilemma: Each VPN has its own routing and forwarding table in the router, so any customer or site that belongs to that VPN is provided access only to the set of routes contained within that table. Any PE-router in an MPLS/VPN..
The Cisco router can be configured to behave like a broadcast medium over NBMA networks. OSPF sends a multicast hello and elects both the designated router and the backup designated router. The designated router provides protection from flooding. All changes are sent via the designated router. By increasing its priority, you can force your most reliable router to become the designated router. This model has a fundamental problem, however, in that it requires constant full mes..
With the introduction of the Versatile Interface Processor (VIP) cards, Cisco made the ultimate step toward a peer multiprocessor architecture. Each VIP card contains its own MIPS r4600 RISC processor, runs a mini-IOS kernel, and has configurable levels of SRAM and DRAM. Although the VIP1 was available for a short time, most of the installed base consists of VIP2s. The distributed features are targeted at the 7500 series (see Figure 5-6), but a VIP1 without distributed featur..
Implementing Standards-Based Per-Hop Behavior
This recipe constructs an approximate implementation of both Expedited Forwarding and Assured Forwarding, while still ensuring that network control packets do not suffer from delays due to application traffic. With the QoS enhancements provided in IOS Version 12.1(5)T and higher, there is a straightforward way to accomplish this using a combination of WRED, CBWFQ, and Low Latency Queuing (LLQ): Router#configure terminal Enter configuration commands, one per line. End w..
TCP is a connection-oriented transport protocol that sends data as an unstructured stream of bytes. By using sequence numbers and acknowledgment messages, TCP can provide a sending node with delivery information about packets transmitted to a destination node. Where data has been lost in transit from source to destination, TCP can retransmit the data until either a timeout condition is reached or until successful delivery has been achieved. TCP can also recognize duplicate me..
