I agree that length = total RIF length = RC + multiple RDs RC = 2 bytes, RD = 2 bytes If the length field doesn't match the RC + RDs length then the RIF is invalid David Johnstad wrote: > 8 bytes is correct. > > In the Route Control field: Length indicates the total lenght (in bytes) > of the entire RIF > Using your example 0601.00A1.00B2.00C0 > 2 2 2 2 Total= 8 bytes > This is a invalid RIF > 0801.00A1.00B2.00C0 > 2 2 2 2 Total= 8 bytes > This is a valid RIF > > -----Original Message----- > From: Fred Ingham [mailto:[EMAIL PROTECTED]] > Sent: Wednesday, April 25, 2001 11:19 PM > To: [EMAIL PROTECTED] > Subject: Re: Test is in 2 hours and I'm having difficulties with RIF > [7:2040] > > Sure hope he didn't believe your answer. 8 is correct - the total > number of bytes in the RIF. > > Fred. > > Wilbo Waggins wrote: > > > > I believe that the 8 bytes is wrong. An RD is 12 bits for the ring, > and 4 > > bits for the bridge number. This is 16 bits which is 2 bytes. 2 > bytes for > > each ring, bridge combination or RD. It has to be 6. > > > > No wonder why the CCIE exam is such a pain in the butt. The > documentation > > and learning material stinks. > > > > ""Michael Bambic"" wrote in message > > [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > > > I'm having an issue with several different view on RIF decoding. > > > > > > One place says this: > > > If I have a RIF of > > > 0610 00A1 00B2 00C0 > > > This is valid because in binary the RC fields say: > > > 000 00110 0 001 0000 > > > Which means: > > > RC = 6 bytes of information which equates to 3 Ring/Bridge combo's > read > > from > > > left to right and a length of 1500 > > > RD = Ring 10 to Bridge 1 to Ring 11 to Bridge 2 to Ring 12 to Bridge > 0 > > which > > > is always the last bridge > > > > > > Another place says this: > > > If I have a RIF of > > > 0810 00A1 00B2 00C3 > > > RC fields say: > > > 000 01000 0 001 0000 > > > RC = 8 bytes of information which equates to 3 Ring/Bridge combo's > read > > from > > > left to right with a length of 1500 > > > RD = Ring 10 to Bridge 1 to Ring 11 to Bridge 2 to Ring 12 to Bridge > 0 > > which > > > is always the last bridge > > > > > > WHICH IS CORRECT? > > > 8 bytes = 3 ring/bridge combo's or > > > 6 byes = 3 ring/bridge combo's > > > > > > If I look at the RD it is 6 byes which makes me believe the first > example > > is > > > correct, however at http://www.cisco.com/warp/public/100/46.html and > the > > > CCIEprep token ring it shows the 8 bytes = 3 ring/bridge combo's. > > > > > > I understand everything else but I will miss every RIF decode > question if > > I > > > don't figure this out. > > > Thanks! > > > Mike Bambic > > > Lead Mentor > > > Phoenix Branch > > > 602-955-5888 > > > Cisco Regional Business Development Manager > > > TechSkills > > > www.techskills.com > > > [EMAIL PROTECTED] > > > > > > [GroupStudy.com removed an attachment of type application/ms-tnef > which > > had > > > a name of winmail.dat] > > > FAQ, list archives, and subscription info: > > http://www.groupstudy.com/list/cisco.html > > > Report misconduct and Nondisclosure violations to > [EMAIL PROTECTED] > > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: > http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=2094&t=2094 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
