MAC address table vs. CAM table

MAC address table vs. CAM table. How they are different?

I don't believe there is a difference as such. CAM simply refers to the way the switch uses memory (in a content-addresable) manner to look up the MAC address to port association.
Paresh

Similar Messages

  • MAC address and the CAM entries on the Layer 3 FWSM(Transparent mode)

    Hi,
    With refrence of Cisco Secure Firewall Services Module (FWSM) of Cisco Press book it's mentioned that
    "While configuring the transparent mode in FWSM, it is important to specify the MAC address and the CAM entries on the Layer 3 next hop device of FWSM."
    This part of configuration is not very much clear to me please let me know the logic of this things
    The following are two examples:
    Layer 3 Device A (PFC) at the Outside Security Domain
    ! IP address of the next hop for the outside security domain
    interface Vlan20
    mac-address 0000.0000.0001
    ip address 10.10.1.1 255.255.255.0
    ! Specify the IP address and MAC address at the first hop layer 3 interface
    ! of the inside security domain
    arp 10.10.1.21 0000.0000.0001 ARPA
    Layer 3 Device B at the Inside Security Domain
    ! IP address of the next hop for the inside security domain
    interface Vlan21
    mac-address 0000.0000.0021
    ip address 10.10.1.21 255.255.255.0
    ! Specify the IP address and MAC address defined at the first hop interface
    ! of the outside security domain
    arp 10.10.1.21 0000.0000.0002 ARPA
    Regards
    Chris

    Check the serial # reported by Sys Info against the serial # printed on the bottom of the case. I bet they are not the same. The service center did not change the serial # on that new Logic board to match the REAL serial number of your Mac.
    So when you try to go to the MAS it looks like a completely different Mac which is not registered under your Apple ID.
    If the above is true, the serials being different, then you need to take it back and have that changed to your REAL serial number.

  • Show Mac Address Table in ASR9k running XR

    I'm trying to find a Mac Address in the ASR9k table.  We have a server with multiple mac addresses and we need to know what MAC is being learned by what interface.
    Thank you,

    Use the command
    show l2vpn forwarding bridge-domain <group_number>:<domain_name> mac-address location 0/x/CPU0
    or
    show l2vpn forwarding bridge-domain mac-address location 0/x/CPU0

  • Mac Address Tracing - CatOS

    I have noticed a lot of bad traffic coming from one particular computer on the network. Normally not a big deal, I found the MAC Address in my DHCP Table, logged into a switch, did a 'sh mac-address-table address <mac address>', found what port it was connected to (it was another switch), I then did a 'sh cdp neighbor detail' got the ip address, telneted to that switch, rinsed and repeated... until I hit a switch that had CatOS.
    My question is how do I do this same type of thing on CatOS? I know how to get everything else except which port it is on like the 'sh mac-address-table address <mac address>' command gives me.

    just type show cam it will clearly tell where the mac-address is residing.
    eg. lets say that 6509--->2950---->(my pc)
    in 6509 type show cam
    it show some thing like this...
    Cat6509> (enable) sh cam 00:02:B3:87:EA:10
    * = Static Entry. + = Permanent Entry. # = System Entry. R = Router Entry.
    X = Port Security Entry $ = Dot1x Security Entry
    VLAN Dest MAC/Route Des [CoS] Destination Ports or VCs / [Protocol Type]
    194 00-02-b3-87-ea-10 4/7 [ALL]
    on 4/7 2950 is connected, in that again you type the pc mac address.
    2950#sh mac-address-table address 00-02-b3-87-ea-10
    Mac Address Table
    Vlan Mac Address Type Ports
    194 0002.b387.ea10 DYNAMIC Fa0/2
    Total Mac Addresses for this criterion: 1
    which means the pc is connected on fasethernet 0/2 port.
    hope this helps,
    rate this post.

  • Multi-MAC Address to One IP Attack?

    I had posted something earlier but have more information.
    Earlier I asked if you could have multiple IP addresses mapped to the same MAC-Address in the ARP table.
    Based on wire captures I have found that it is no problem for the WGB1310 or for the Cisco 6500 to have this. However, I am hearing that there is a special security feature in the WiSM or WLC that sees this as an attempted ATTACK on the network.  I would see a ping come through the 6500, over the wireless network and hit my virtual IP address and I would see the virtual IP address respond.  However, the response did not make it back to the sending PC because of this issue.
    And so now my application fails.
    Does anyone know of this feature or if I can disable it on the WiSM?  This is crushing my deployment.

    Ok, an update on this.
    I have a layer 3 switch on every train.
    I am thinking I can just keep the 1310 in WGB mode near my end user and keep the other 1310 in AP mode for the link back to the WiSM, plug the ethernet interface of my WGB into the layer 3 switch then on the other side of the switch I will have a /28 network.
    On the WLC/WiSM I would then create a static route for each /28 to the external interface (by which I mean the interface on the same subnet as the WLC) of the layer 3 switch.
    I think I would also have to create a static route on the 6500 for these networks as well since it needs to know that they exist on the other side of the WiSM.
    Make sense?
    Can't wait to test it out.
    James

  • ARP detstination mac-address 0000.0000.0000

    Internet Router--->3550 Switch-->Nortel Contivity
    63.169.164.134-->63.169.164.140--> 63.169.140.136
    All the devices are having public IP addresses and are in Vlan 100.
    Sometimes the Internet Router is not able to ping or connect to the Contivity where as the switch is able to access both the devices (Internet Rtr & Contivity).
    While checking on the switch & Internet rtr i capture the following logs.
    Switch#sh log
    Mar 25 11:17:17.990 EDT: IP ARP: creating incomplete entry for IP address: 63.169.164.136 interface Vlan100
    Mar 25 11:17:17.990 EDT: IP ARP: sent req src 63.169.164.140 0012.800b.a780,dst 63.169.164.136 0000.0000.0000 Vlan100
    Internet RTR#sh log
    Mar 25 11:17:17 EDT: IP ARP: rcvd req src 63.169.164.140 0012.800b.a780, dst 63.169.164.136 GigabitEthernet0/1
    Mar 25 11:20:54 EDT: IP ARP: rcvd req src 63.169.164.138 0018.b964.66fc, dst 63.169.164.145 GigabitEthernet0/1
    We have done a static ARPA entry in internet rtr for Contivity but still the issue remains same. The moment the issue persists again i tried to clear the arp on switch but it didn't make router to get reply from Contivity when i did the same clear arp-cache on internet rtr, it started getting communicate with Contivity.
    I am not able to find the solution of this issue and the reason for that, now every time i have to do clear ip arp-cache on rtr whenever the issue comes down.
    Also i want to understand the situation when a dest mac-address can be 0000.0000.0000.
    Any help on this will be appreciated.
    Thanks.

    Bhupesh
    If a router receives a packet to forward to a destination address which is on a local LAN but the destination IP address does not appear in the arp table then the router creates an incomplete entry in the ARP table (it is incomplete because the router does not have the destination MAC address and is attempting to learn it). The router creates the incomplete entry in the ARP table and sends an ARP request. If the router receives an ARP response then it puts the destination MAC address into the ARP table and the entry is now complete. If no ARP response is received the router will purge the incomplete entry. Note that the router can not forward the IP packet that caused the incomplete entry and the router will drop that IP packet.
    In considering the problem with contivity I had been assuming that the problem was on rtr. But it occurs to me that it is quite possible (and even likely given the fact that you mention which is that in the problem the switch can still ping contivity ) that the problem is on contivity. I wonder if for some reason contivity gets an incorrect MAC for rtr? I suspect that clear arp on rtr fixes the problem because as it clears the arp table I believe that rtr will send a gratuitous arp which refreshes the ARP entry in contivity. In the time of the problem can you check the table in contivity?
    HTH
    Rick

  • A mac address for a Vlan

    Could someone please tell me if a mac address is getting created as a result of creating a layer 2 Vlan?
    Thanks..

    Just tested this on a Cisco 3750 on my desk.
    I had VLAN 1 Shutdown.
    I did a show mac-address-table and there was no MAC for Vlan 1.
    I unshut the VLAN 1 interface (no IP configured on it) and now there IS a mac-address entry in my table.
    Understand that this is different than just adding say VLAN 10 to your vlan database or something like that.
    If all you did was add a VLAN (re, not a virtual interface) to your vlan config then it will NOT create a mac-address entry.
    However, if you create an interface, it will.
    So the answer to your question is, it depends on what you are trying to do.
    Hope that helps!
    James

  • EPC3010 MAC Address Aging

    The spec sheet does not say a lot about the bridge forwarding table.
    Could someone tell me the number of MAC addresses that the forwarding table can hold.
    Also are there SNMP OIDs for controlling how quickly entries in the forwarding table will time out, or for deleting entries in the forwarding table?

    The Add option allows you to add Ethernet MAC addresses for devices that might pass traffic through the bridge. If no addresses are added through the Add option, the bridge learns the first eight MAC addresses that pass through its Ethernet Port. Subsequently, only data from those addresses is allowed to pass through the bridge.
    Caution: The first MAC address you add should be that of the PC you are using to Telnet or browse to
    the bridge.
    You should add MAC addresses if there are more than eight Ethernet devices attached to the hub to
    which the bridge is connected. This ensures that the selected devices communicate through the bridge. After an address is added, the bridge won't learn any more addresses. You must type each MAC address you wish to have communicate through the bridge (up to eight).
    Once you enter the first MAC address, the MAC addresses of every other device that you want the
    bridge to communicate with must be entered. The process is not automatic and the bridge will no longer "learn" any addresses. The addresses must be manually entered.

  • Invalid MAC Address Format Error

    I have a WRT54GR with a 54USB Wireless Adaptor...and I am trying to put my PC MAC Address in the Allow Table so that this is the only MAC Address that can access my network...it is recognising my 54USB Adaptor MAC Address in the Table, so I select this, and add it to the table to allow access, and it comes up with Invalid MAC Address Format.... 
    Anybody know why this is happening...I have tried adding it automatically and typing it in manually still the same.  I use ':' between the numbers/characters not '-'.
    Any help greatly appreciated....
    Thanks
    Smartie27.

    Try it in the form  xxxxxxxxxxxx  and see if that works, or maybe just xx xx xx xx xx xx

  • Block curtain MAC-addresses on my WRT54GL

    Hello
    I use a Linksys WRT54GL for my wireless setup in my apartment. I have noticed that there sometimes are unknown MAC-addresses in "DHCP Clients Table". I guess it is my neighbours or someone on the street.
    Am I able to block a curtain MAC-address, so I precent them to connect to my network. And how?
    Best regards,
    MAthias

    Under the Wireless tab,click on the Wireless Mac Filter>>>>choose the option enable and click on the option "document.write("Prevent PCs listed below from accessing the wireless network.") Prevent PCs listed below from accessing the wireless network" and then,click on Edit Mac Filter List to enter the Mac Address which you want to prevent.

  • Mac-address-table synchronize

    Dears
    Would like your assistance please regarding command "mac-address-table synchronize"
    My understanding is that it syncs CAM table between different DFCs & RSP PFC
    So If we are having only one DFC there would be no need for this command. It will only be useful in case we are having several DFCs or there is a communication between DFC and ports connected in RSP.
    1- Correct ?
    2- Is SVI interface considered to be part of DFC or PFC ?
    I am asking this cause if part of PFC then this command would be needed
    Many Thanks
    Regards
    Sherif Ismail

    Sherifismail,
    I see that its already been answered anyway again:
    My understanding is that it syncs CAM table between different DFCs & RSP PFC
    ==Answer is yes.
    So If we are having only one DFC there would be no need for this command. It will only be useful in case we are having several DFCs or there is a communication between DFC and ports connected in RSP.
    1- Correct ? 
    Answer: No you still required. else sometime you might see the mac address present in the software and not on the module.
    2- Is SVI interface considered to be part of DFC or PFC ?
    I am asking this cause if part of PFC then this command would be needed
    Answer: I would believe it would be part of PFC.
    HTH

  • MAC Address-Table Move Update Feature

    Hi guys
    Does 6500 SUP720/2T support MAC Address-Table Move Update Feature?
    I cannot find it in anywhere..
    Thanks very much!
    QXZ

    Hi,
    Please refer following link :
    http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a00807347ab.shtml
    CAM
    —All Catalyst switch models use a CAM table for           Layer 2 switching. As frames arrive on switch ports, the source MAC addresses           are learned and recorded in the CAM table. The port of arrival and the VLAN are           both recorded in the table, along with a timestamp. If a MAC address learned on           one switch port has moved to a different port, the MAC address and timestamp           are recorded for the most recent arrival port. Then, the previous entry is           deleted. If a MAC address is found already present in the table for the correct           arrival port, only its timestamp is updated.
    regards,
    Ajay Kumar

  • ARP table not populating mac address for previously reachable IP address

    Router has been online and working fine with one BGP neighbor for almost 2 years and no downtime.  2 weeks ago, added a 2nd BGP peer.  Everything worked fine for 2 weeks, then all of a sudden yesterday the 2nd BGP peer is disconnected and does not come back.  ISP checks and sees everything looks fine on their end.  We cannot even ping each other now.
    Upon investigation, the ARP table is not even populating the MAC address for the BGP peer IP anymore (same local subnet).  Stays "incomplete" in the table no matter what we do, including clearing arp table, changing IP address, etc.
    Plug a laptop directly into the 2nd BGP peer FE port and replicate the IP addressing.  Laptop cannot ping Router, but Router CAN ping laptop.  Check ARP table, but STILL no mac address assigned and now not even the ARP table showing "incomplete".
    Thinking it could be the FE interface, switch to the 2nd FE interface and perform same laptop test, this time with arbitrary IP addressing.  Now cannot ping each other, no MAC in ARP table.
    End up rebooting the router and lo-and-behold, everything is working normally again.  2nd BGP peer peers up instantly.
    I should also mention that the 1st BGP peer worked flawlessly throughout, taking all the Internet load and having no issues throughout.
    Also, the FE ports for the 2nd BGP peer are on an HWIC FE card plugged into the router.  The 1st BGP peer is plugged into the built-in GE interface.  2901 running: c2900-universalk9-mz.SPA.151-4.M4.bin
    Lastly, no router resource issues, no error messages, no logs.  Just the BGP peer disconnecting.
    I have never, in 20 years working with Cisco routers seen something like this before.  This is the most fundamental aspect of IP and Ethernet that was not working.
    Has anyone ever seen this behavior before??
    Here is the router config (IP's changed):
    version 15.1
    service timestamps debug datetime msec localtime show-timezone
    service timestamps log datetime msec localtime show-timezone
    service password-encryption
    service internal
    service sequence-numbers
    boot-start-marker
    boot-end-marker
    logging buffered 150000
    aaa new-model
    aaa authentication login LAUTHEN local
    aaa authentication login TAUTHEN local group tacacs+ enable
    aaa authorization console
    aaa authorization exec LAUTHOR local if-authenticated
    aaa authorization exec TAUTHOR local group tacacs+ if-authenticated
    aaa session-id common
    clock timezone PST -8 0
    clock summer-time PDT recurring
    no ipv6 cef
    no ip source-route
    ip cef
    no ip domain lookup
    multilink bundle-name authenticated
    username ubiadmin privilege 15 secret 4 .JbeuWXuZvchrG0OL.5BftFtqrrEyxcnVHn5rIuCnTk
    username umitsnoc01 privilege 15 secret 4 cUmoRUjey9O1x.wk9S.kleX.iAAhCwihupr6Z98p6OA
    redundancy
    ip ssh version 2
    track 1 interface GigabitEthernet0/0 line-protocol
    class-map match-any AutoQoS-VoIP-RTP-Trust
     match access-group name SIP-Media-INBOUND
    class-map match-any AutoQoS-VoIP-Control-Trust
     match ip dscp cs3
     match ip dscp af31
    class-map match-any Customer-Voice
     match access-group name Customer-VPNs
    class-map match-any media
     match access-group name SIP-Media
    class-map match-any signaling
     match access-group name SIP-Signaling
    policy-map AutoQoS-Policy-Trust
     class AutoQoS-VoIP-RTP-Trust
      priority percent 70
     class AutoQoS-VoIP-Control-Trust
      bandwidth percent 5
     class class-default
      fair-queue
    policy-map queue
     class signaling
      bandwidth percent 5
     class media
      priority percent 50
     class Customer-Voice
      priority percent 40
     class class-default
      fair-queue
    policy-map shape
     class class-default
      shape average 10000000
      service-policy queue
    interface Embedded-Service-Engine0/0
     no ip address
     shutdown
    interface GigabitEthernet0/0
     description BGP Peer 1
     ip address 2.2.2.2 255.255.255.252
     no ip redirects
     ip flow ingress
     ip flow egress
     duplex auto
     speed auto
     service-policy output shape
    interface GigabitEthernet0/1
     description LAN
     ip address 1.2.3.4 255.255.255.0
     no ip redirects
     ip flow ingress
     ip flow egress
     standby 255 ip 1.2.3.1
     standby 255 priority 105
     standby 255 preempt
     standby 255 mac-address 1a2b.3c4d.5e6f
     standby 255 track 1 decrement 10
     duplex auto
     speed auto
     service-policy output AutoQoS-Policy-Trust
    interface FastEthernet0/0/0
     description BGP Peer 2
     ip address 1.1.1.1 255.255.255.252
     ip flow ingress
     ip flow egress
     duplex full
     speed 100
     service-policy output shape
    interface FastEthernet0/0/1
     no ip address
     shutdown
     duplex auto
     speed auto
    router bgp 7777
     bgp router-id 2.2.2.2
     bgp log-neighbor-changes
     network 1.2.3.0 mask 255.255.255.0
     neighbor 1.1.1.2 remote-as 5555
     neighbor 1.1.1.2 update-source FastEthernet0/0/0
     neighbor 1.1.1.2 prefix-list L3-DEFGW in
     neighbor 1.1.1.2 route-map L3-LPREF-IN in
     neighbor 2.2.2.1 remote-as 6666
     neighbor 2.2.2.1 ebgp-multihop 2
     neighbor 2.2.2.1 update-source GigabitEthernet0/0
     neighbor 2.2.2.1 send-community
     neighbor 2.2.2.1 prefix-list COLO-DEFGW in
     neighbor 2.2.2.1 route-map COLO-LPREF-IN in
     neighbor 2.2.2.1 route-map COLO-OUT out
    ip forward-protocol nd
    ip bgp-community new-format
    ip as-path access-list 5 permit _5555_
    ip as-path access-list 5 deny .*
    ip as-path access-list 10 permit ^6666$
    no ip http server
    no ip http secure-server
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     top 50
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    ip route 0.0.0.0 0.0.0.0 1.1.1.2 254 name L3
    ip route 0.0.0.0 0.0.0.0 2.2.2.1 255 name COLO1
    ip route 10.0.0.0 255.0.0.0 10.10.10.10 name FW_OUTSIDE
    ip tacacs source-interface GigabitEthernet0/1
    ip access-list standard SNMP_SOURCES
     permit 12.12.12.0 0.0.0.255
     deny   any log
    ip prefix-list L3-DEFGW seq 5 permit 0.0.0.0/0
    ip prefix-list COLO-DEFGW seq 5 permit 0.0.0.0/0
    ip prefix-list COLO-LPREF-OUT seq 5 permit 1.2.3.0/24
    route-map COLO-LPREF-IN permit 5
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     set local-preference 250
    route-map COLO-LPREF-IN permit 10
     set local-preference 150
    route-map COLO-LPREF-IN permit 20
    route-map COLO-OUT permit 10
     match ip address prefix-list COLO-LPREF-OUT
     set as-path prepend 7777 7777 7777
     set community 29795:1004
    route-map COLO-OUT permit 20
    route-map L3-LPREF-IN permit 10
     match as-path 10
     set local-preference 200
    route-map L3-LPREF-IN permit 20
     set local-preference 150
    snmp-server enable traps snmp authentication linkdown linkup coldstart warmstart
    snmp-server enable traps vrrp
    snmp-server enable traps flowmon
    snmp-server enable traps transceiver all
    snmp-server enable traps ds1
    snmp-server enable traps call-home message-send-fail server-fail
    snmp-server enable traps tty
    snmp-server enable traps license
    snmp-server enable traps envmon
    snmp-server enable traps ethernet cfm cc mep-up mep-down cross-connect loop config
    snmp-server enable traps ethernet cfm crosscheck mep-missing mep-unknown service-up
    snmp-server enable traps flash insertion removal
    snmp-server enable traps mac-notification
    snmp-server enable traps aaa_server
    snmp-server enable traps cef resource-failure peer-state-change peer-fib-state-change inconsistency
    snmp-server enable traps memory bufferpeak
    snmp-server enable traps config-copy
    snmp-server enable traps config
    snmp-server enable traps config-ctid
    snmp-server enable traps event-manager
    snmp-server enable traps hsrp
    snmp-server enable traps cpu threshold
    snmp-server enable traps rsvp
    snmp-server enable traps syslog
    snmp-server enable traps vtp
    snmp-server enable traps ipsla

    When you were checking the ARP table was there an entry for Fast0/0/0?
    HTH
    Rick

  • Mac address table on a PIX

    What am i missing?
    pixfirewall# show mac-address-table
                       ^
    ERROR: % Invalid input detected at '^' marker.
    [EDIT: karat is under the A in mac ]
    pixfirewall# sh ver
    Cisco PIX Security Appliance Software Version 8.0(4)
    Device Manager Version 6.1(3)
    Compiled on Thu 07-Aug-08 19:42 by builders
    System image file is "flash:/image.bin"
    Config file at boot was "startup-config"
    pixfirewall up 175 days 11 hours
    Hardware:   PIX-525, 256 MB RAM, CPU Pentium III 600 MHz
    Flash E28F128J3 @ 0xfff00000, 16MB
    BIOS Flash AM29F400B @ 0xfffd8000, 32KB
    0: Ext: Ethernet0           : address is 000d.28f9.62a5, irq 10
    1: Ext: Ethernet1           : address is 000d.28f9.62a6, irq 11
    2: Ext: Ethernet2           : address is 000d.8810.a620, irq 11
    3: Ext: Ethernet3           : address is 000d.8810.a621, irq 10
    4: Ext: Ethernet4           : address is 000d.8810.a622, irq 9
    5: Ext: Ethernet5           : address is 000d.8810.a623, irq 5
    Licensed features for this platform:
    Maximum Physical Interfaces  : 6
    Maximum VLANs                : 25
    Inside Hosts                 : Unlimited
    Failover                     : Disabled
    VPN-DES                      : Enabled
    VPN-3DES-AES                 : Enabled
    Cut-through Proxy            : Enabled
    Guards                       : Enabled
    URL Filtering                : Enabled
    Security Contexts            : 0
    GTP/GPRS                     : Disabled
    VPN Peers                    : Unlimited
    This platform has a Restricted (R) license.
    Serial Number: 807234146
    Running Activation Key: 0x6ab205ba 0x986d4239 0xf56523af 0x76f3d58b
    Configuration last modified by enable_15 at 12:58:08.130 EDT Thu May 16 2013
    pixfirewall# show mac-address-table
                       ^
    ERROR: % Invalid input detected at '^' marker.

    Hi,
    Command Modes The following table shows the modes in which you can enter the command:
    Command Mode
    Firewall Mode
    Security Context
    Routed
    Transparent
    Single
    Multiple
    Context
    System
    Privileged EXEC
    Source:
    http://www.cisco.com/en/US/docs/security/asa/asa80/command/reference/s4.html#wp1448364
    - Jouni

  • Force mapping to a specific MAC address a multicast IP address in ARP cache table with netsh

    Hi all,
    I would like to know if there is any solution (netsh option, registry entry, whatever...) to force mapping a given MAC address to a multicast IP address (224.x.y.z) in my ARP cache table.
    I am doing the following:
    netsh.exe interface ip add neighbors "Ethernet" "224.224.xxx.yyy"
    "00-80-EE-UU-VV-WW"
    But the entry in the ARP table is substitued by the calculated multicast MAC@ corresponding to my multicast IP@ :
    netsh.exe interface ip show neighbors "Ethernet"
    Interface 12 : Ethernet
    Internet Address  
    Physical Address Type
    224.0.0.22 
    01-00-5e-XX-YY-ZZ 
    static
    224.224.yyy.zzz 
    01-00-5e-UU-VV-WW 
    static
    (For information, calculation of the Multicast MAC Address is described in RFC1112§6.4 -> The MAC@ equals 01-00-5e + the last 23 digits of the multicast MAC Address)
    My problem is that I'm not using an Ethernet network but an AFDX (used on Airbus A380, Boeing 787 Dreamliner, by the NASA...). This network topology is a deterministic Ethernet. The network must know accurately where each network packet is going. Thus...
    the multicast MAC@ cannot be accepted and packet destinated to that MAC@ are not going anywhere.
    So, I must match accurately my multicast IP@ to my MAC@ (00-80...).
    It used to work with Windows XP (which was not doing any "magical" MAC@ substitution on multicast IP@), but since Windows Vista, netsh is doing the substitution described above. Is there any way to disable this substitution or force my IP
    to MAC mapping in ARP table? And of course, I'm not using XP anymore ;)... but a tablet with Windows 8.1.
    Thanks for any help.
    Cheers,
    Olivier.

    Hi,
    The article you pointed me to is just an explanation of what I said in my original post : "Multicast MAC Address is described in RFC1112§6.4".
    But, as I said in my original post, this is true ONLY for Ethernet network. And I am NOT on an Ethernet network.
    So MAC address automatic calculation for my IP address done by Windows/netsh/arp is wrong in my case. The calculation Windows is doing is correct ONLY for Ethernet network. Since I am not on Ethernet, I don't want these calculations, and I'm looking for
    a solution to disable them.
    So, the underlying question is : "Is Microsoft/netsh/arp able to handle other network's type than Ethernet ?"
    Thanks,
    Olivier Dupré.

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