LSA Types in OSPF

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LSA Types in OSPF

OSPF relies on several types of Link State Advertisements (LSAs) to communicate link state information between neighbours. A brief review of the most applicable LSA types:

LSA Types:

• Type 1 - Represents a router
• Type 2 – Network LSA (who is my DR)
• Type 3 - A network link summary all ABR (internal route)
• Type 4 - Represents an ASBR (who is my ASBR)
• Type 5 - A route external to the OSPF domain
• Type 6 – Group membership Multicasting
• Type 7 - Used in stub areas in place of a type 5 LSA

List of Protocols and there Port numbers

Protocol	Port number	Protocol Used
FTP File Transfer Protocol	20 - for data 21 - for connection establishing	TCP/UDP TCP
SFTP Secure File Transfer Protocol	22	TCP
SSH Secure Shell Protocol	22	TCP
Telnet	23	TCP
SMTP Simple Mail Transfer Protocol	25	TCP