rfc2329.txt

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RFC 2329	      OSPF Standardization Report	      April 1998



				       Imple-	Inter-
	    Feature		       mented	operated   Deployed
	    _______________________________________________________
	    OSPF areas		       10	10	   10
	    Stub areas		       10	10	   9
	    Virtual links	       10	9	   8
	    Equal-cost multipath       10	7	   8
	    NBMA support	       9	8	   7
	    CIDR addressing	       8	5	   6
	    OSPF MIB		       8	5	   5
	    Cryptographic auth.	       3	2	   1
	    Point-to-Multipoint	ifc.   6	3	   4


		    Table 1: Implementation of OSPF features


    Table 2 indicates the size of the OSPF routing domains that	vendors
    have tested. For each size parameter, the number of	responders and
    the	range of responses (minimum, mode, mean	and maximum) are listed.


       Parameter		    Responses	Min   Mode   Mean   Max
       _________________________________________________________________
       Max routers in domain	    7		30    240    460    1600
       Max routers in single area   7		20    240    380    1600
       Max areas in domain	    7		1     10     16	    60
       Max AS-external-LSAs	    9		50    10K    10K    30K


		       Table 2:	OSPF domain sizes tested


    Table 3 indicates the size of the OSPF routing domains that	vendors
    have deployed in real networks. For	each size parameter, the number
    of responders and the range	of responses (minimum, mode, mean and
    maximum) are listed.














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RFC 2329	      OSPF Standardization Report	      April 1998



       Parameter		    Responses	Min   Mode   Mean   Max
       _________________________________________________________________
       Max routers in domain	    8		20    350    510    1000
       Max routers in single area   8		20    100    160    350
       Max areas in domain	    7		1     15     23	    60
       Max AS-external-LSAs	    6		50    1K     2K	    5K


		      Table 3: OSPF domain sizes deployed


    In an attempt to ascertain the extent to which OSPF	is currently
    deployed, vendors were also	asked in January 1998 to provide
    deployment estimates. Four vendors of OSPF routers responded, with a
    total estimate of 182,000 OSPF routers in service, organized into
    4300 separate OSPF routing domains.

4.  Protocol Security

    All	OSPF protocol exchanges	are authenticated. OSPF	supports
    multiple types of authentication; the type of authentication in use
    can	be configured on a per network segment basis. One of OSPF's
    authentication types, namely the Cryptographic authentication
    option, is believed	to be secure against passive attacks and provide
    significant	protection against active attacks. When	using the
    Cryptographic authentication option, each router appends a "message
    digest" to its transmitted OSPF packets. Receivers then use	the
    shared secret key and received digest to verify that each received
    OSPF packet	is authentic.

    The	quality	of the security	provided by the	Cryptographic
    authentication option depends completely on	the strength of	the
    message digest algorithm (MD5 is currently the only	message	digest
    algorithm specified), the strength of the key being	used, and the
    correct implementation of the security mechanism in	all
    communicating OSPF implementations.	 It also requires that all
    parties maintain the secrecy of the	shared secret key.

    None of the	OSPF authentication types provide confidentiality. Nor
    do they protect against traffic analysis. Key management is	also not
    addressed by the OSPF specification.










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RFC 2329	      OSPF Standardization Report	      April 1998


    For	more information, see Sections 8.1, 8.2, and Appendix D	of
    [Ref1].

References

    [Ref1]  Moy, J., "OSPF Version 2", RFC 2178, July 1997.

    [Ref2]  Hinden, B.,	"Internet Routing Protocol Standardization
	    Criteria", RFC 1264, October 1991.

    [Ref3]  Moy, J., "OSPF Version 2", RFC 1583, March 1994.

    [Ref4]  Baker, F., and R. Coltun, "OSPF Version 2 Management
	    Information	Base", RFC 1850, November 1995.

    [Ref5]  Moy, J., "OSPF Protocol Analysis", RFC 1245, August	1991.

    [Ref6]  Moy, J., "Experience with the OSPF Protocol", RFC 1246,
	    August 1991.

    [Ref7]  Varadhan, K., Hares	S., and	Y. Rekhter, "BGP4/IDRP for IP--
	    -OSPF Interaction",	RFC 1745, December 1994.

    [Ref8]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

Security Considerations

    Security considerations are	addressed in Section 4 of this memo.

Author's Address

    John Moy
    Ascend Communications, Inc.
    1 Robbins Road
    Westford, MA 01886

    Phone: [phone]
    Fax:   [phone]
    EMail: [e-mail]













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RFC 2329	      OSPF Standardization Report	      April 1998


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