TCP Reset Question

I have a query on TCP/IP communication. Let's say I have a cisco device running with http server disabled. If I send a TCP syn packet to the device with destination port 80/443(any non-listening port), will the device respond with TCP RESET? Or will it simply drop the packet without any acknowledgement?

I think this will be different from device to device:
ASA will drop denied connection to services it does not run, to make it send resets use the command "service resetoutside" to send reset to a denied TCP packet to outside interface.
Access Points will by default reset
Routers  will by default reset
Switches will by default reset
Regards,
PS. Please rate and mark as right

Similar Messages

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  • Does cisco router support "tcp reset" mesg when the traffic blocked by access lit ?

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  • TCP RESET - CISCO IPS 4240 in IDS Mode - Block Teamviewer

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  • TCP Reset not working

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  • IDSM-2 disable tcp reset and RiskRating

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  • What should i do if i can't remember my security question's answer because i do not have a safety email for apple to send the reset question link? my safety email got deleted :(

    what should i do if i can't remember my security question's answer because i do not have a safety email for apple to send the reset question/answer link? my safety email got deleted

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  • IPS 4240 : TCP Reset didn't work properly

    hello all,
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    port: 2269
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    port: 23
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    000000 FF FB 01 FF FB 03 FF FD 18 FF FD 1F 0D 0A 0D 0A ................
    000010 55 73 65 72 20 41 63 63 65 73 73 20 56 65 72 69 User Access Veri
    000020 66 69 63 61 74 69 6F 6E 0D 0A 0D 0A 50 61 73 73 fication....Pass
    000030 77 6F 72 64 3A 20 FF FA 18 01 FF F0 word: ......
    fromAttacker:
    000000 FF FD 01 FF FD 03 FF FB 18 FF FB 1F FF FB 1F FF ................
    000010 FA 1F 00 50 00 1E FF F0 FF FA 18 00 41 4E 53 49 ...P........ANSI
    000020 FF F0 74 65 73 74 61 74 74 61 63 ..testattac
    riskRatingValue: 75
    interface: ge0_0
    protocol: tcp
    reagards,
    John.

    I had this issue when I was preparing for my
    CCIE security back in 2006 with IDS version
    4.1 so it may or may not apply to your
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    objective: From RouterX, telnet to RouterA.
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    to RouterX thus reset the connection.
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    monitor session 1 source vlan 4
    monitor session 1 destination interface f0/5 ingress vlan 4
    that will do the trick.
    what I also found out from my preparation of
    the lab is that is that the IDS will send
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    the other 20% of the time, even though I
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    event viewer. I also confirmed this
    by running tcpdump on the IDS itself (yes,
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    not figure out why it behaved this way.
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  • IDSM-2 TCP reset

    Hi,
    I have been trying to figure out how to get TCP reset working in IDSM-2.
    Switch config,
    monitor session 2 destination intrusion-detection-module 9 data-port 1
    monitor session 2 source remote vlan 99
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    Hi,
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    Thanks and Regards,
    Thulasi Shankar

  • Configure TCP Reset in IDSM

    I am using module IDSM (in promicuous mode). I don't know I can configure TCP reset in IDSM or not?
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    Thank you very much.
    Duy Khang

    Hi everyone,
    If you know the configuration, please answer me?
    Thank you very much

  • Verify TCP reset is actually working

    How do I see if the TCP reset is working,
    I have IDM, IEV, IDS MC, and for some reason I cannot locate the information
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    Hi,
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    5. Scroll to the right, and look under 'TCP Reset Sent'. If the stated value is 'true', the IDS has performed the tcp reset to the attack event.
    Cheers!
    AK

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