The simple explanation
You all know this person, the person who somehow manages to make every conversation about himself. His favourite song? “Me, Myself & I.” Of course it is.
The technical explanation
LSA 1 is basically the OSPF narcissist. He talks about his own links, his own connections and his own costs. Me. Me. Me. And that is actually a pretty good way to remember what a Type 1 LSA does.
Every OSPF router generates a Type 1 LSA, also called a Router LSA. It describes the router itself and its connections inside the OSPF area. In simple terms, it tells the other routers:
This is me, these are my links, and this is what they cost.
Type 1 LSAs are flooded throughout the area, but they do not cross the area boundary. If another area needs information about those networks, that is where other LSA types come into the story.
So if you only remember three things about LSA 1:
- Every OSPF router creates one.
- It describes the router and its own links inside the area (Me, me and me)
- It never leaves the area.
Basically: a narcissist with very strict geographical boundaries.
Protocol reference: RFC 2328 (OSPFv2). NSSA reference: RFC 3101.
logic
"She is such an LSA1! It's all about her. Her views and her connections. So annoying.
Example
An ABR attached to Area 0 and Area 10 originates a different Router LSA inside each area.