Question: Does OSPF Uses TCP Or UDP?

Why do we use OSPF protocol?

The main advantage of a link state routing protocol like OSPF is that the complete knowledge of topology allows routers to calculate routes that satisfy particular criteria.

This can be useful for traffic engineering purposes, where routes can be constrained to meet particular quality of service requirements..

Does OSPF use hop count?

Like EIGRP, OSPF bases its metric by default on link bandwidth, so that OSPF makes a better choice than simply relying on the router hop-count metric used by RIP. But OSPF uses much different internal logic, being a link-state routing protocol rather than a distance vector protocol.

What OSI layer is BGP?

BGP is a Layer 4 protocol that sits on top of TCP. It is much simpler than OSPF, because it doesn’t have to worry about the things TCP will handle. Peers that have been manually configured to exchange routing information will form a TCP connection and begin speaking BGP.

How OSPF cost is calculated?

Open Shortest Path First (OSPF) uses “Cost” as the value of metric and uses a Reference Bandwidth of 100 Mbps for cost calculation. The formula to calculate the cost is Reference Bandwidth divided by interface bandwidth. For example, in the case of 10 Mbps Ethernet , OSPF Metric Cost value is 100 Mbps / 10 Mbps = 10.

What port does OSPF use?

RIP uses the User Datagram Protocol (UDP) as its transport protocol, and is assigned the reserved port number 520. Open Shortest Path First (OSPF) is a link-state routing protocol. OSPF does not use a TCP/IP transport protocol (UDP, TCP), but is encapsulated directly in IP datagrams with protocol number 89.

Does BGP use TCP or UDP?

Unlike all other routing protocols, BGP uses TCP as its transport protocol. Discuss the consequences of running BGP over UDP.

Which layer is OSPF?

OSI layer designation IS-IS runs on the data link layer (Layer 2) Open Shortest Path First (OSPF) is encapsulated in IP, but runs only on the IPv4 subnet, while the IPv6 version runs on the link using only link-local addressing. IGRP, and EIGRP are directly encapsulated in IP.

How does OSPF protocol work?

OSPF is a routing protocol. Two routers speaking OSPF to each other exchange information about the routes they know about and the cost for them to get there. … OSPF routers rely on cost to compute the shortest path through the network between themselves and a remote router or network destination.

Why OSPF is preferred over BGP?

BGP is considered to be more flexible as well as scalable than OSPF and it would be also used on a larger network. OSPF would be used to determine the fastest route whereas the BGP would be putting emphasis on determining the best path. Well, Because OSPF stub areas which would be a total mess to configure.

How do I enable OSPF?

To enable OSPF on a Cisco router and advertise interfaces, the following tasks are required:Use the command router ospf process ID to start OSPF.Use the network command to enable the interfaces.Identify area assignments.(Optional) Assign the router ID.

IS IS protocol vs OSPF?

Comparison with OSPF. Both IS-IS and Open Shortest Path First (OSPF) are link-state protocols, and both use the same Dijkstra algorithm for computing the best path through the network. … While OSPF was natively built to route IP and is itself a Layer 3 protocol that runs on top of IP, IS-IS is an OSI Layer 2 protocol.

What port is BGP?

BGP neighbors, called peers, are established by manual configuration among routers to create a TCP session on port 179. A BGP speaker sends 19-byte keep-alive messages every 60 seconds to maintain the connection. Among routing protocols, BGP is unique in using TCP as its transport protocol.

Is OSPF a distance vector protocol?

OSPF is not a distance-vector protocol like RIP, but a link-state protocol with a set of metrics that can be used to reflect much more about a network than just the number of routers encountered between source and destination. In OSPF, a router attempts to route based on the “state of the links.”

Is OSPF a layer 3 protocol?

Another reason OSPF still dominates is because OSPF is a layer 3 protocol, while IS-IS is a layer 2 protocol. This means that OSPF information is exchanged using data packets that can be routed, while IS-IS is not. Data packets from layer 3 protocols can traverse routers.

What is the default cost of OSPF?

Default values: 100 Mbps—The default cost is 5.

Where is BGP used?

Border Gateway Protocol (BGP) is used to Exchange routing information for the internet and is the protocol used between ISP which are different ASes. The protocol can connect together any internetwork of autonomous system using an arbitrary topology.

What is Lsdb in OSPF?

The LSDB (Link State Database) is the database that OSPF builds and is based on the information that it has found in LSAs (Link State Advertisements). The LSDB is synchronized between routers within the same area.

What is the maximum hop count for OSPF?

224In the OSPF routing protocol, the maximum hop count is 224.