ACL TCAM and LOUs in Catalyst 6500

Document

Apr 30, 2011 1:20 PM
Apr 30th, 2011

   1. Purpose

Explain how Access Control Lists (ACL) configured in Catalyst 6500 fit into its ACL TCAM and LOUs, and also to optimize the ACL configurations.

2. Understanding the usage of ACL TCAM :

       The ACL TCAM is organized into series of VALUES (aka Entries) and MASK.

clip_image002.gif

Fig 1: ACL TCAM Organization – Masks, Values and Results

Let us consider an example ACL and see how the switch populates the TCAM.

Example:

ip access-list extended EXAMPLE

            permit  ip         any host 10.1.2.100

            deny    ip         any host 10.1.68.101

            deny    ip         any host 10.33.2.25

            permit  tcp       any any    eq 22

            deny    tcp       any any    eq 23

            deny    udp      any any    eq 514

            permit  tcp       any any    eq 80

            permit  udp      any any    eq 161

First three ACEs check destination IP address only and rest of the ACEs check destination TCP/UDP port. So, the switch need two Masks. For every mask allocated, we can have maximum of 8 entries, as shown in the above figure.

For the above mentioned ACL, the TCAM will look like as mentioned below. A bit value of 0 in mask means that the corresponding bit position in the value is not compared with the actual traffic being classified (also known as don’t care bit).

Mask is 104 bits length and compares Source-IP, Destination-IP, L4 port type (TCP/UDP), Source L4 port and Destination L4 port.

clip_image002.gif

      Fig 2: Usage of TCAM Masks and Value

3.  ACL TCAM and Logical Operation Units (LOUs)

ACLs use Logical Operations like:

Lesser than (lt)

Greater than (gt)

Equal to (eq)

Not equal to (neq)

Range

The Catalyst 6500 hardware provides Logical Operations in Hardware do these operations. The ACL hardware has 128 hardware LOUs and it is a global resource. Global LOUs are divided equally for source port and destination port operations and 2 LOUs needed to match port range. Totally,  we can do 32 source port range matches and 32 destination port range matches in hardware.

Also per ACL we have 10 bits called L4Ops that select from the global LOUs, in order to perform a port operation for a given ACE within the ACL.

So across all ACLs combined we can do 32 source port range (or TCP flag) matches and 32 destination port range (or TCP flag) matches in hardware using the LOUs, and for any specific ACL we can do 10 port range (or TCP flag) operations using the LOUs.

If there are more port ranges in the ACL than the available LOUs and L4OPs, they are expanded in software into equivalent entries. This is known as PORT EXPANSION.

LOUs.jpg

Fig 3: Logical Operation Units in Catalyst 6500

4. Monitoring the utilization of TCAM and LOUs

6500A# show tcam counts

          Used        Free        Percent Used       Reserved

           ----        ----        ------------       --------

Labels:     20        4076            0


ACL_TCAM

--------

  Masks:   3549         547           86                    72

Entries:  19740       13028           60                   576


QOS_TCAM

--------

  Masks:      4        4092            0                    18

Entries:     22       32746            0                   144


    LOU:     64          64           50

  ANDOR:      1          15            6

  ORAND:      0          16            0

    ADJ:      0        2048            0


6500A# show platform hardware capacity acl

ACL/QoS TCAM Resources

  Key: ACLent - ACL TCAM entries, ACLmsk - ACL TCAM masks, AND - ANDOR,

       QoSent - QoS TCAM entries, QOSmsk - QoS TCAM masks, OR - ORAND,

       Lbl-in - ingress label, Lbl-eg - egress label, LOUsrc - LOU source,

       LOUdst - LOU destination, ADJ - ACL adjacency

Module ACLent ACLmsk QoSent QoSmsk Lbl-in Lbl-eg LOUsrc LOUdst  AND  OR  ADJ

     5    60%    86%     0%     0%     1%     1%     50%   50%   0%  0%   0%


6500A# sho tcam lou

LOU #  Opcode  Port#   CapMap Count    Ace Count

-----  ------  -----   ------------    ---------

    0       1   1024            10        1944

   64       1  33701             7           9

   65       4  33433             7           9

   66       1   1024             6          36

<snip>


Opcode: LT = 1, GT = 2, NEQ = 3 and RANGE = 4.

5. Optimization the usage of TCAM resources:

5.1 Defining ACEs and Order dependency:

Consider an ACL (similar to the one discussed in Section 2 above) starts with 9 ACEs checking destination IP address and 5 ACEs checking destination L4 port, then we need totally 3 masks.

Mask (104 bits)

Value

Result

00000000 FFFFFFFF   00 0000 0000

< totally 8   entries >

< Permit or Deny   >

00000000 FFFFFFFF   00 0000 0000

< 1 entry >

< Permit or Deny   >

00000000 00000000   00 0000 FFFF

< totally 5   entries >

< Permit or Deny   >

It is NOT correct to directly correlate number of ACEs configured to number of masks/entries used.

As you might be aware, an ACL and the TCAM are order dependent. For 2 ACEs to share the same mask besides having the don’t care bits in the same locations they need to be adjacent to each other in the ACL definition. One example of entries that can mask share would be say a subnet:

Permit any host 192.10.10.0

Permit any host 192.10.10.1

192.10.10.0 192.10.10.1 both have the same mask 255.255.255.254 (the last bit is don’t care).

So the 2 entries result in 1 TCAM entry with 1 mask: Permit 192.10.10.0 255.255.255.254

If in another ACL adjacent 2 entries are:

Permit 192.11.11.0

Permit 192.11.11.1

This would result in 1 TCAM entry with 1 mask 255.255.255.254 and since the mask is the same we will use the second of the 8 entries corresponding to this mask.

TCAM entry for the above 2 will look thus:

Mask (104 bits)

Value

Result

00000000 FFFFFFFE   00 0000 0000

xxxxxxxx   192.10.10.0 xx xxxx xxxx

Permit

xxxxxxxx   192.11.11.0 xx xxxx xxxx

Permit

Definition of ACEs and its order determines the usage of ACL TCAM Masks and entries.

5.2 Defining Logical Operations in an ACL to optimize usage of TCAM/LOUs

Let us consider following ACL entry:

Permit any host 192.10.10.1 tcp range 1020 1023 any

If we cannot use the LoUs, it should be expanded it out to individual ACEs.

Permit any host 192.10.10.1 tcp 1020 any

Permit any host 192.10.10.1 tcp 1021 any

Permit any host 192.10.10.1 tcp 1022 any

Permit any host 192.10.10.1 tcp 1023 any

A LOU can be referenced by multiple ACEs in the same ACL. Taking our example above, we could have another set of ACEs in the same ACL as

Permit any host 195.1.2.3 tcp range 1020 1023 any

If we had an LOU allocated for the logical operation “range 1020 1023” the 2 ACEs will share it. Every usage of such Logical operation within an ACL is called an instance.

When expanding an ACL for lack of LOUs, the number of ACEs it expands to depends on 2 things:

  1. Expansion factor (say m) – number of ACEs required to emulate the port range
  2. The number of instances (say n) – number of places where that port range is used.

After expansion the ACEs will increase by product of m and n. (m * n)

This document has an Appendix (Section 8) that lists methods to calculate the expansion factor (m)

6. Optimizing Port Expansion

(1) Calculate a priority (weight) to each Logical Operation.


Calculated priority for a particular port range is based on the following factors:

a)     How many ACEs will an ACE with this port range expand to if an LOU cannot be used (expansion factor)? We need to include and consider any "gt"/"lt" operations used in the same way as other port ranges. These should be put in hardware since they may expand to a large number of aces.

b)    How many ACE’s use this port range (ref count)?


The priority for each range will be determined by (expansion factor – 1) * ref count.


(2) Determine what LOUs are already allocated in hardware (for other ACLs or from the current successful HW programming of a given ACL). From this exercise we determine if the current LoU allocation is optimal or not. We want High priority operations (identified in Step1 above) to be allocated in hardware.


(3) ACEs with operations on TCP flags must always be allocated an LOU and hence are      highest priority.


(4)  It  is possible to eliminate the need for a L4OP. As an example say an ACE of,

Permit any host 192.10.10.1 lt 1025

could be redefined as

Permit any host 192.10.10.1 eq 1024

Permit any host 192.10.10.1 lt 1024

The latter does not consume any LoU since the range 0 to 1023 can be represented using TCAM mask and hence no L4OP.


(5) Make sure one L4OP is available for TCP flags (within the first 10) for the "established" TCP flags match. Configure "permit tcp any any established" to make sure the TCP flags also gets allocated a L4OP. [ similarly, configure one ACE that use a given high priority port range, and do same thing for all port ranges, based on their priority ]

(6) Please be careful because you do not want to alter the behavior of the ACL by rearranging the ACEs. Consider adding some dummy ACEs (such as "deny tcp host 0.0.0.0 host 0.0.0.0 range 3500 3530") which are matching basically some invalid traffic at the top of the ACL for the critical ranges. Basically these ACEs do not have any effect except making sure the port range is allocated L4OP/LOU.


7. Summary of ACL modification procedure

  • Start with the largest ACL and work one ACL at a time
  • Pick all ACE's w/ TCP flags and move at least one ACE with TCP flags at the top.
  • Calculate expansion factor * ref count for each port range (including lt / gt)
  • Pick the top 9 highest weighted (priority) ranges for using the L4OPs for this ACL.
  • One ACE per range now has to be moved up in the ACL (place after the first ACE with tcp established flag) or a dummy ACE with this range should be inserted.
  • Repeat for each of the remaining ACL's (Keep in mind some ranges may already be available from previous ACL's but we still have only 10 L4OP bits)
  • Use the “show tcam counts” command to check the mask utilization percentage to repeat the optimization of the ACLs in order to try and achieve the desired mask  utilization. These repetitive steps should be performed on the non-production physical dry-run catalyst 6500.

8. APPENDIX

8.1. Calculating the Expansion factor (m)

8.1.1 Mathematical way to calculate Expansion factor (m)


The expansion factor depends on the actual values since it is dependent on the bit position which is determined by the binary representation of the layer 4 port values. Explained below is the mathematics behind calculating the expansion factor.

(a) Expansion factor (m) for Greater Than (GT) case


To calculate a Greater Than case first convert the port number to binary. Add leading 0s until the total number of bits are 16 (since the Layer4 port numbers are maximum 16 bits)


Example: permit any host 192.10.1.1 gt 35 any


The binary representation of 35 (after adding leading 0 to make the number of bits 16) is


0000 0000 0010 0011


GT 35 expands into (- below means don’t care)

1--------------- covers range 32768 to 65535

-1-------------- covers range 16384 to 32767

--1------------- covers range 8192 to 16383

---1------------ covers range 4096 to 8191

----1----------- covers range 2048 to 4095

-----1---------- covers range 1024 to 2047

------1--------- covers range 512 to 1023

-------1-------- covers range 256 to 511

--------1------- covers range 128 to 255

---------1------ covers range 64 to 127

----------11---- covers range 48 to 63

----------1-1--- covers range 40 to 47

----------1--1-- covers range 36 to 39

So in case of GT the expansion factor m is the number of 0s in the binary representation of the number (after adding leading 0s to make the number of bits 16).


(b) Expansion factor (m) for Less Than (LT) case


To calculate a less than case first convert the port number to binary.

Example: permit any host 192.10.1.1 gt 35 any

The binary representation of 35 is 10 0011

LT 35 (i.e. entries from 0 to 34) expands into: (where – means don’t care)

0----- covers range from 0 to 31

10000- covers 32, 33

100010 covers 34


So in case of LT the expansion factor m is the number of 1s in the binary representation of the number.

(c) Expansion factor (m) for ranges

Let us consider the example of range 50 62

First convert them into binary representation:


62 = 11 1110

50 = 11 0010

If you take a look you see that the leading (most significant) 2 bits are same and they differ in only the last 4 bits. We need to disregard the same bits and concentrate on the bits that follow (including) the first bit where they start to differ (shown in orange above).


Form the diff group for the two numbers which are the lower bits including the orange one above.

In our example the diff group for 62 is 1110 and for 50 it is 0010


To get the worst case value for the expansion factor (m) count the number of 1 in the binary representation of higher number, limited to the group of bits that differ (aka diff group). In our example that would be for 62 and the number of 1s is 3. Then look at the number of bits that differ for the lower number and count the number of 0s. That in our example would be for 50 and the count of 0s is 3. Now get the sum of those 2 which is 6. Hence the worst case expansion for this range is 6.


For most cases this approximation may be good enough.


However, to get the exact number we need to weed out the overlaps. The overlap is found by comparing the first entries from the GT and LT expansion of the diff group and if they overlap then we remove them.


To find the overlaps take the diff group from the higher number and apply the LT algorithm to it. That gives (group LT):

0---

10--

110-

Then we place all 1 in the don’t care (-) above to give (group LT#):

0111

1011

1101

Also form a group LT## where we place all 0 in the don’t care (-) above to give (group LT##)

0000

1000

1100


Now we take the diff group from the lower number and apply the GT algorithm to it (no need to expand it to 16 bits). That gives (group GT):


1---

01--

0011

Next we place all 0 in the don’t care (-) above to give (GT#):


1000

0100

0011

Now compare the first entry from LT# (0111) with all the entries in GT#. If it is greater than any one of those entries (in this case it is greater than 0011), take the corresponding entry in LT## (which is 0011) and compare it with all entries in GT#. Since 0000 is less than 0011 the first entry 0--- in LT is part of overlap and can be discarded.


Next compare the first entry from GT# (1000) with all the entries in LT##. Since 1000 is less than at least one entry in the group LT## (in this case 1100) it is also part of the overlap and can be safely discarded.


So the accurate expansion count is 6 – 2 (since we are discarding 2 entries due to overlap) = 4


The actual expanded entries would look like this (you need to put back the bits besides the diff group):

11 10-- range 56 to 59 (from the LT group)

11 110- range 60 to 61 (from the LT group)

11 01-- range 52 to 55 (from the GT group)

11 0011 equal 51 (from the GT group)


If only Source (or destination) ports are used the worst case expansion is 16.


If range operation on both source and destination ports are used then first calculate the expansion factor for source and destination port ranges individually (say src_m and dest_m) and the final expansion factor is the product of the two (m = src_m * dest_m). Consequently, the worst case expansion factor is 256 (16 * 16), when ranges are used for both: source and destination ports.


8.1.2 Alternate Process to calculate Expansion factor (m)

Since all the above mathematical calculations are coded in an catalyst 6500 the easiest way to get the expansion factor (m)  is to use the Catalyst 6500 to do the work. Hence better to use a staging box (rather than a production box).


Create a test ACL and define first 12 ACEs to use logical operations (this will lock in the available L4OPs and LoUs per ACL and force the FM to do the ACL expansion)


Now define an ACE with the range (or logical operation) for which you want to calculate the expansion factor as the 13th ACE of this test ACL.


Apply the test ACL to an interface (needs to be in Admin up state. The line protocol state does not matter). If using a production box please make sure that this interface has tcam priority low configured so that it does not pull out any TCAM entries from the TCAM.


Do a show fm interface <int> (where int is the interface to which the test ACL was applied above).


Look at the output to get the expansion factor.


Example:

Router#sh ip access-lists test

Extended IP access list test

    10 permit tcp any any range 10 ftp-data

    20 permit tcp any any range ftp-data 30

    30 permit tcp any any range 30 40

    40 permit tcp any any range 40 50

    50 permit tcp any any range 50 60

    60 permit tcp any any range 60 gopher

    70 permit tcp any any range gopher www

    80 permit tcp any any range www 90

    90 permit tcp any any range 90 100

    100 permit tcp any any range 100 pop3

    110 permit tcp any any range pop3 120

    120 permit tcp any any range 120 130


If we want to find the expansion factor for example range 14000-14026:


Router(config)#ip access-list extended test

Router(config-ext-nacl)#permit tcp any any range 14000 14026

Router(config-ext-nacl)#end


Router#sh ip access-lists test

Extended IP access list test

    10 permit tcp any any range 10 ftp-data

    20 permit tcp any any range ftp-data 30

    30 permit tcp any any range 30 40

    40 permit tcp any any range 40 50

    50 permit tcp any any range 50 60

    60 permit tcp any any range 60 gopher

    70 permit tcp any any range gopher www

    80 permit tcp any any range www 90

    90 permit tcp any any range 90 100

    100 permit tcp any any range 100 pop3

    110 permit tcp any any range pop3 120

    120 permit tcp any any range 120 130

    130 permit tcp any any range 14000 14026


Router(config)#int f1/48

Router(config-if)#ip access-group test in

Router(config-if)#end


Router#sh fm int f1/48

Interface: FastEthernet1/48 IP is enabled

  hw_state[INGRESS] = not reduced, hw_state[EGRESS] = not reduced

  mcast = 0

  priority = 0

  flags = 0x4

  parent[INGRESS] = none

  inbound label: 104


    Feature IP_ACCESS_INGRESS:

        ACL: test

-----------------------------------------------------------------------------

FM_FEATURE_IP_ACG - Acl Name: test      Direction:Ingress

=============================================================================

DPort  - Destination Port  SPort  - Source Port       Pro    - Protocol

PT     - Packet Type       DPT    - Dst. Packet Type  SPT    - Src. Packet Type

X      - XTAG              TOS    - TOS Value         Res    - VMR Result

RFM    - R-Recirc. Flag    MRTNPC - M-Multicast Flag  R      - Reflexive flag

       - F-Fragment flag          - T-Tcp Control     N      - Non-cachable

       - M-More Fragments         - P-Mask Priority(H-High, L-Low)

Adj.   - Adj. Index        C      - Capture Flag      T      - M(Mask)/V(Value)

FM     - Flow Mask         NULL   - Null FM           SAO    - Source Only FM

DAO    - Dest. Only FM     SADA   - Sour.& Dest. Only VSADA  - Vlan SADA Only

ISADA  - Intf. SADA        FF     - Full Flow         VFF    - Vlan Full Flow

IFF    - Intf. FF          F-VFF  - Either FF or VFF  IFF-FF - Either IFF or FF

A-VSD  - Atleast VSADA     A-FF   - Atleast FF        A-VFF  - Atleast VFF

A-SON  - Atleast SAO       A-DON  - Atleast DAO       A-SD   - Atleast SADA

SHORT  - Shortest          ISADA-L- ISADA Least       FF-L   - FF Least

IFF-L  - IFF Least         A-SFF  - Any short than FF A-EFF  - Any except FF

A-EVFF - Any except VFF    SA-L   - Source Least      DA-L   - Dest. Least

SADA-L - SADA Least        FF-LESS- FF Less           N-FF   - Not FF

N-IFF  - Not IFF           A-LVFF - Any less than VFF FULL   - Full Pkt Type

EUI    - EUI 64 Pkt Type   EMBD   - Embedded Pkt Type ELNK   - EUI Link Overlap

ESIT   - EUI Site Overlap  LINK   - Link Pkt Type     SITE   - Site Pkt Type

ERR    - Flowmask Error

+----+-+---------------+---------------+-----+-----+---+---+-+---+------+----+------+


|Indx|T|  Dest Ip Addr | Source Ip Addr|DPort|SPort|Pro|RFM|X|ToS|MRTNPC|Adj.|  FM  |

+----+-+---------------+---------------+-----+-----+---+---+-+---+-----+----+------+

1    V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

2    V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    10 - 20

      TM_PERMIT_RESULT

3    V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

4    V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    20 - 30

      TM_PERMIT_RESULT

5    V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

6    V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    30 - 40

      TM_PERMIT_RESULT

7    V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

8    V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    40 - 50

      TM_PERMIT_RESULT

9    V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

10   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    50 - 60

      TM_PERMIT_RESULT

11   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

12   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    60 - 70

      TM_PERMIT_RESULT

13   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

14   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    70 - 80

      TM_PERMIT_RESULT

15   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

16   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    80 - 90

      TM_PERMIT_RESULT

17   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

18   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE    90 - 100

      TM_PERMIT_RESULT

19   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

20   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE   100 - 110

      TM_PERMIT_RESULT

21   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

22   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE   110 - 120

      TM_PERMIT_RESULT

23   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

24   V         0.0.0.0         0.0.0.0     0     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 000 0   0

      Destination: RANGE   120 - 130

      TM_PERMIT_RESULT

25   V         0.0.0.0         0.0.0.0     0     0   6 -F- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0 255 010 0   0

      TM_PERMIT_RESULT

26   V         0.0.0.0         0.0.0.0 14026     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0 65535     0 255 000 0   0

      TM_PERMIT_RESULT

27   V         0.0.0.0         0.0.0.0 14000     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0 65520     0 255 000 0   0

      TM_PERMIT_RESULT

28   V         0.0.0.0         0.0.0.0 14016     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0 65528     0 255 000 0   0

      TM_PERMIT_RESULT

29   V         0.0.0.0         0.0.0.0 14024     0   6 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0 65534     0 255 000 0   0

      TM_PERMIT_RESULT

30   V         0.0.0.0         0.0.0.0     0     0   0 --- 0   0 ----L- ---- SHORT

      M         0.0.0.0         0.0.0.0     0     0   0 000 0   0

      M         0.0.0.0         0.0.0.0     0     0   0 000 0   0

      TM_L3_DENY_RESULT

The entries 26, 27, 28, 29 are the expanded ACEs to cover the port range for 14000 - 14026. The last (30) is for the default deny ip any any ACE. So the expansion factor m in this case is 4.

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Posted April 30, 2011 at 1:20 PM
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