... • run intra-AS routing
protocol with all other
routers in AS
• also responsible for routing
to destinations outside AS
– run inter-AS routing
protocol with other
gateway routers
...
... b. An application produces output in terms of 2-Mbyte bursts. Each burst has a 20 milliseconds
duration, and bursts occur at a constant interval of 500 milliseconds (i.e., 2 in a second). The
application lasts for 2 seconds. It is connected to an 8-Mbps network through a token bucket.
Suppose the to ...
... avoids unnecessary costs and disruptions caused by switch upgrades.
Use the optical layer to provide recovery. Our routing is well suited to packet-switched traffic, but
does not rely on a specific protocol such as IP or ATM. Instead, our access scheme operates below such
protocols. Recovery is perf ...
... Network Operation Center (NOC) collects information from individual nodes
NOC carries out the least cost routing algorithms.
NOC distributed the routing information to individual nodes.
The above steps are carried out periodically.
Flooding
A node sends/relays a message along all its outgoing links. ...
... accessible via a time suitable network path.
• When the clock fails the slave needs to find a new clock
• Initially clock-slave pairing will be statically configured.
• As the number of slaves increases and the demands on
time quality/availability increase static configuration does
not scale.
...
... everyone knows how to route to him on shortest path). Then using the label the central node knows the next step, after
that we are assured to be in the cluster of node v, from there using the routing tables we can route to v on shortest path.
The table size at each node is proportional to the number ...
... Best path is selected by a routing protocol based on the value or metric
it uses to determine the distance to reach a network.
A metric is the value used to measure the distance to a given network.
Best path to a network is the path with the lowest metric.
Dynamic routing protocols use their ...
... • RIP – Routing Information Protocol – treats each network the same (assigns
the same cost for each network)
• OSPF – Open Shortest Path First protocol – assigns a cost for passing
through a network based on the type of service required – routes through the
network can have different cost – each rou ...
... autonomous system (IGP)
Full CIDR and subnet support
Authenticated message exchange
Allows routes to be imported from outside the
autonomous system
Uses link-status (SPF) algorithm
Support for multi-access networks (e.g.,
...
... dissimilar LANs and WANs running at different
transmission speeds, using a variety of protocols
• Routers are protocol-dependent
• Routing protocols provide rules for communication
between routers and help them determine the best
path between two nodes
• Gateways are combinations of networking
hardw ...
... VRRP advertisement messages to the VRRP multicast IP address, where all backup nodes listen. If a backup node
does not receive an advertisement message for 4 advertisement intervals, it becomes the master node.
Advanced VRRP – Redundancy and Load Sharing
With the basic router setup you can get redun ...
... requirements, no meta data, no replication – same with Random
(but random gives an edge in low mobility environments) – best
suited to achieve highest power savings
Contrary would be epidemic – highest delivery ratio, high
latency – not desirable even with high resources (storage and
power)
All thre ...
... —Before D crashes, Routers A and C inform B that it
can reach network 5 through them with a cost of 16
• So after D crashes, B never thinks that it can reach network
5 through A or C
...
Routing is the process of selecting best paths in a network. In the past, the term routing also meant forwarding network traffic among networks. However, that latter function is better described as forwarding. Routing is performed for many kinds of networks, including the telephone network (circuit switching), electronic data networks (such as the Internet), and transportation networks. This article is concerned primarily with routing in electronic data networks using packet switching technology.In packet switching networks, routing directs packet forwarding (the transit of logically addressed network packets from their source toward their ultimate destination) through intermediate nodes. Intermediate nodes are typically network hardware devices such as routers, bridges, gateways, firewalls, or switches. General-purpose computers can also forward packets and perform routing, though they are not specialized hardware and may suffer from limited performance. The routing process usually directs forwarding on the basis of routing tables, which maintain a record of the routes to various network destinations. Thus, constructing routing tables, which are held in the router's memory, is very important for efficient routing. Most routing algorithms use only one network path at a time. Multipath routing techniques enable the use of multiple alternative paths.In case of overlapping/equal routes, algorithms consider the following elements to decide which routes to install into the routing table (sorted by priority):Prefix-Length: where longer subnet masks are preferred (independent of whether it is within a routing protocol or over different routing protocol)Metric: where a lower metric/cost is preferred (only valid within one and the same routing protocol)Administrative distance: where a route learned from a more reliable routing protocol is preferred (only valid between different routing protocols)Routing, in a more narrow sense of the term, is often contrasted with bridging in its assumption that network addresses are structured and that similar addresses imply proximity within the network. Structured addresses allow a single routing table entry to represent the route to a group of devices. In large networks, structured addressing (routing, in the narrow sense) outperforms unstructured addressing (bridging). Routing has become the dominant form of addressing on the Internet. Bridging is still widely used within localized environments.
