Overlapping/Duplicate AS-External-LSA IDs

I was reading OSPF: Anatomy of an Internet Routing Protocol by John T. Moy today and I came across an issue with AS-external LSA Link-State IDs. The LSA uses the network address as the identifier. If one router was to generate multiple Type 5 LSA's with the same network number but different masks, only 1 would be advertised because the LSA ID would be the same.

The book was published in 1998 and at the time there was no way of dealing with this. After doing this lab, I realized there was a way and it had since been documented in Appendix E of RFC 2328:

RFC 2328 Appendix E

Here I create 3 static routes, that all end up with the same network number and would normally have the same LSA ID:

R1(config)#ip route 192.9.0.0 255.255.0.0 Null0  
R1(config)#ip route 192.9.0.0 255.255.254.0 Null0
R1(config)#ip route 192.9.0.0 255.255.255.0 Null0
R1(config)#router ospf 1
R1(config-router)#redistribute static subnets 

Let's see what the LSA IDs are:

R1#sho ip osp database | inc 192.9
192.9.0.0       1.1.1.1         246         0x80000001 0x00933F 0
192.9.0.255     1.1.1.1         149         0x80000001 0x00933F 0
192.9.1.255     1.1.1.1         234         0x80000001 0x00834F 0
R1#

R1#sho ip ospf database external 192.9.0.0

            OSPF Router with ID (1.1.1.1) (Process ID 1)

                Type-5 AS External Link States

  LS age: 14
  Options: (No TOS-capability, DC)
  LS Type: AS External Link
  Link State ID: 192.9.0.0 (External Network Number )
  Advertising Router: 1.1.1.1
  LS Seq Number: 80000003
  Checksum: 0x8F41
  Length: 36
  Network Mask: /16
        Metric Type: 2 (Larger than any link state path)
        TOS: 0 
        Metric: 20 
        Forward Address: 0.0.0.0
        External Route Tag: 0

The router gives the last 2 networks the broadcast address of that respective network as the Link State ID. The /16 network got the network address as the ID. I wonder if order of operations has anything to do with it

R1(config)#no ip route 192.9.0.0 255.255.0.0 Null0
R1(config)#no ip route 192.9.0.0 255.255.254.0 Null0
R1(config)#no ip route 192.9.0.0 255.255.255.0 Null0
R1(config)#ip route 192.9.0.0 255.255.255.0 Null0   

Ok, so now the /24 is the only in there and it is using 192.9.0.0 as its ID:

R1#sho ip osp database external 192.9.0.0

            OSPF Router with ID (1.1.1.1) (Process ID 1)

                Type-5 AS External Link States

  LS age: 36
  Options: (No TOS-capability, DC)
  LS Type: AS External Link
  Link State ID: 192.9.0.0 (External Network Number )
  Advertising Router: 1.1.1.1
  LS Seq Number: 80000001
  Checksum: 0x933F
  Length: 36
  Network Mask: /24
        Metric Type: 2 (Larger than any link state path)
        TOS: 0 
        Metric: 20 
        Forward Address: 0.0.0.0
        External Route Tag: 0

What happens if we add a /16 now?

R1(config)#ip route 192.9.0.0 255.255.0.0 Null0

R1#sho ip osp database external 192.9.0.0

            OSPF Router with ID (1.1.1.1) (Process ID 1)

                Type-5 AS External Link States

  LS age: 12
  Options: (No TOS-capability, DC)
  LS Type: AS External Link
  Link State ID: 192.9.0.0 (External Network Number )
  Advertising Router: 1.1.1.1
  LS Seq Number: 80000002
  Checksum: 0x9140
  Length: 36
  Network Mask: /16
        Metric Type: 2 (Larger than any link state path)
        TOS: 0 
        Metric: 20 
        Forward Address: 0.0.0.0
        External Route Tag: 0

R1#

The /16 stold the ID from the /24!

R1#sho ip osp database | inc 192.9       
192.9.0.0       1.1.1.1         45          0x80000002 0x009140 0
192.9.0.255     1.1.1.1         45          0x80000001 0x00933F 0