From: Carlos G Mendioroz (tron@huapi.ba.ar)
Date: Sun Jul 11 2004 - 19:17:07 GMT-3
Ty,
ToS byte is used in two different ways:
PPPDTRUU like 3 bits for precedence, some flags and unused bits.
or (new style)
DDDDDDEE like 6 bits for DSCP code and 2 bits for ECN (explicit
congestion notification).
Precedence 5 would be 101 in binary, so it would end being 10100000, or
A0 (as you said) but because bits are:
1 0 1 0 0 0 0 0
*8 4 2 1 8 4 2 1
=8 0 2 0 0 0 0 0
A 0
cause 8 + 2 = A
Precedence 7 would be
1 1 1 0 0 0 0 0
E 0
barrerj1@hotmail.com wrote:
> Thanks for the info and for taking time to go over the details,
>
>
> JB
>
> -----Original Message-----
> From: Ty [mailto:tycampbell@comcast.net]
> Sent: Sunday, July 11, 2004 3:43 PM
> To: ccielab@groupstudy.com; barrerj1@hotmail.com
> Subject: Re: tos values
>
> I couldn't find it, but I did figure it
>
> it works like this..
>
> say the ip precedece is 5 and you want to conver it to ToS
>
> ToS uses 8 bits in hex ie 00000000 split into 2 parts 0000 0000
>
> ip precedence is 5 ..so that would be the fifth bit in ToS which would
> equal 0001 0000
>
> beaking down the ToS bits 0 0 0 0 0 0 0 0
> E C A 8 4 2
> 1
>
> there is not a match to worry about for the 8th bit, as ip precedence
> only
> goes to 7
>
> R7(config)#access-list 107 permit ip any any precedence ?
> <0-7> Precedence value
> critical Match packets with critical precedence (5)
> flash Match packets with flash precedence (3)
> flash-override Match packets with flash override precedence (4)
> immediate Match packets with immediate precedence (2)
> internet Match packets with internetwork control precedence (6)
> network Match packets with network control precedence (7)
> priority Match packets with priority precedence (1)
> routine Match packets with routine precedence (0)
>
> going back to ip precedence of 5 would equal 0001 0000 in ToS
>
> therefore the ToS of A0 would equal an ip precendece of 5
>
> another example... ip precedence of 7 would equal ToS E0
>
> 7 = 0100 0000
> ----- Original Message -----
> From: <barrerj1@hotmail.com>
> To: "'Ty'" <tycampbell@comcast.net>
> Sent: Sunday, July 11, 2004 3:10 PM
> Subject: RE: tos values
>
>
>
>>Can you tell me where you find the info?
>>
>>Thanks
>>JB
>>
>>
>>
>>-----Original Message-----
>>From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
>
> Of
>
>>Ty
>>Sent: Sunday, July 11, 2004 3:04 PM
>>To: Ty; ccielab@groupstudy.com
>>Subject: Re: tos values
>>
>>I figured it out
>>
>>tos is done in hex
>>
>>so if and ip precednce of 5 were to be converted to tos then it would
>
> be
>
>>00010000 in hex...this would make the tos A0
>>
>>Thanks!!
>>
>>
>>
>>----- Original Message -----
>>From: "Ty" <tycampbell@comcast.net>
>>To: <ccielab@groupstudy.com>
>>Sent: Sunday, July 11, 2004 2:55 PM
>>Subject: tos values
>>
>>
>>
>>>I have searched the DOC CD, but cannot find a formula or table to
>>
>>convert
>>ip
>>
>>>precedence values to tos.
>>>Does anyone know where this is on the DOC CD ?
>>>
>>>Thanks!!
>>>
>>>
>>
> _______________________________________________________________________
>
>>>Please help support GroupStudy by purchasing your study materials
>>
>>from:
>>
>>>http://shop.groupstudy.com
>>>
>>>Subscription information may be found at:
>>>http://www.groupstudy.com/list/CCIELab.html
>>
>>
> _______________________________________________________________________
>
>>Please help support GroupStudy by purchasing your study materials
>
> from:
>
>>http://shop.groupstudy.com
>>
>>Subscription information may be found at:
>>http://www.groupstudy.com/list/CCIELab.html
>
>
> _______________________________________________________________________
> Please help support GroupStudy by purchasing your study materials from:
> http://shop.groupstudy.com
>
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
-- Carlos G Mendioroz <tron@huapi.ba.ar> LW7 EQI Argentina
This archive was generated by hypermail 2.1.4 : Sun Aug 01 2004 - 10:11:52 GMT-3