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Questions tagged [tap]

The act of passively monitoring network traffic by way of a specialized device directly connected to the network medium. The term can also be used to describe the device itself.

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Which TAP is the right one for my network?

I want to buy a TAP but I'm uncertain which device is the right one for my environment. The command sudo lshw shows the following about my Ethernet: *-network description: Ethernet ...
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Influence of a TAP

I want to use a passive TAP to sniff all the network (100 Mbps full duplex twisted pair). I have two interfaces for sniffing and only one pair for each direction. Will the TAP add any noise? Or if I ...
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Capturing traffic from multiple connections on a switch

Consider the traffic monitoring setup on the bottom of this page: https://www.ntop.org/pf_ring/port-mirror-vs-network-tap/ The two lines of a network tap are connected to a switch which merges the ...
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Capturing traffic on wire from an endpoint

Say I have my computer connected to a router with an Ethernet cable. How do I capture all packets on the wire? (possibly with using some kind of hardware that's much cheaper than another computer) I ...
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1answer
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Sensor to collector communication from SPAN, Inline or TAP

I am trying to figure out which one of the three modes or all would support this. The sensor is a computer running fprobe and pushing UDP traffic (netflow v5) to an IP address in the network. My ...
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Tapping Nexus 5k FEX uplinks

Very similar to this question, we are considering tapping the FEX uplinks that we have running from Top Of Rack to our Nexus 5k core switches. Has anyone had success with tapping those uplinks? I ...
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3answers
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Is there an “active” network tap (not just passive)? [closed]

Passive network taps seem to be pretty simple. What if I want an "active" network tap? Let's say I want to change some HTTP packets, for example add info etc. Another thing that would interest my ...
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1answer
474 views

Is Wifi a broadcast medium?

If wifi/wlan is broadcast medium, can we tap the wifi traffic by just placing our wlan0 into promiscuous mode?. In this way, can we get the source ip and destination ip of the traffic generated by ...
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How to trap message between two servers? [closed]

I have two server one of them sends message in xml format to another server. The number of message varies i.e from 10000/sec to 1 million per second. The other end receives and stores it as file. Both ...
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OpenFlow switching based on a specific ethertype

My goal is to send to a specific interface all ethernet traffic with a special ethertype. I have thus a virtual switch with OpenVSwitch on my interface eth0, and I use tap interfaces to retrieve ...
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2answers
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Building a 3 port network tap (100mbps half-duplex)

I've tried building a network tap with only three ports: the two communicating parties and a tap side. I knew this would force the communicating sides to use at most half-duplex 100mbps, but detection ...
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Cisco Nexus Fabric Extenders with 10G-SFP in path?

We are looking to deploy a new data center build-out with Nexus 7ks and Nexus 2ks(FEX). I know the Nexus 2ks come bundled with the Fabric Extenders to be used to uplink to the Nexus 7ks. Our plan ...
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packet capturing

I am having a hard time understanding certain terminology and setup when it comes to packet capturing. Example. At my company we use NetScout and the various services such as PFS(Packet forwading ...
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Why do network taps have four ports?

I've been looking at a hardware network tap like this one to replace a pseudo-permanent SPAN that's been running on a Catalyst switch. All the taps I find have four interfaces: A, B, and two output ...