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9

I would take a look at iperf. You should be able to use built in reporting in iperf to validate the amount of traffic dropped. iperf is typically ran across the network between two systems. I have iperf3 installed on two CentOS machines, as you can see below, one is configured as the server and the other the client. Install the iperf rpm, start the ...


8

Using a search for "linux ethernet packet generator" gives me packeth as the first hit. packeth Solution: Has both a GUI and CLI version Generates not only UDP, but many other protocols as well, including QinQ Is packaged for RedHat as an rpm, or Debian package netcat and tcpdump Solution: If it was me, I would just do a quick-and-dirty ten second netcat ...


6

Depending on the ASA and license you have, you could use contexts which create virtual ASAs within the ASA. Each is independent of the other. This would also allow you to test ASA configs before putting them on production. Each vlan interface is assigned to a context. Packets coming in are classified (in your situation, via MAC of the vlan interface) and ...


5

Don't trust GNS3 for throughput tests. As soon as you use a router in your topology you are likely only to get 5mb/sec tops, regardless of whether you use a serial, ethernet or fast ethernet interface and regardless of how powerful your PC is. (Note that the performance hit won't be seen if you use a GNS3 switch instead of a router, however, the switches are ...


4

Judging by your switch, I'd say you don't have the budget for a real ethernet tester like those from Fluke Networks. Your switch is Layer 2 (L2) only and doesn't support routing, so you'd need an external router (L3) to move packets between the VLANs. I would conjecture that your random network issues were caused by either bad cabling or mismatch on speed/...


4

A loopback interface is a virtual (i.e. not physical) interface that never goes down, unless you disable it. This way, if you configure an IP on this loopback interface and add it to your OSPF area (or any other routing protocol), it will always be reachable by whatever available/best path exists, provided that your router is not completely isolated. I ...


4

...we learned that every router has a LOOPBACK interface. That is not true. Cisco routers can be configured with loopback interfaces, but they don't have loopback interfaces until you create one. The idea of a loopback interface is that it is a virtual interface which never goes down due to a physical line or network problem. Loopback interfaces can be ...


4

The PSE decides on which pairs power is supplied. A compliant PD needs to be able to use either pairs. Connecting a power supply to the spare pairs (only possible with 10BASE-T and 100BASE-TX) is not compatible with IEEE PoE. While most devices would probably work, some won't, and some may even break. My advice is to use a proper PoE injector and modify it ...


3

EDITED Despite the extended usage of binary in computer world and power of two based units (Byte, 32-bits word etc...), network bandwidth is commonly expressed in power of ten units. So it is (speed_in_Bps * 8) / (10 ^ (3 * 2)) (or /50^3)


3

I'm almost 100% positive that for Cisco switches it would be CDP (Cisco Discovery Protocol) while on other vendors, they would use the industry standard LLDP (Link Layer Discovery Protocol). From CDP, you can get information such as switch port, VLAN, switch name, and link negotiation info (e.g. full vs half duplex) to name a few. I hope this helps.


3

There are a few problems with your premise. First, connecting switch ports to switch ports will either end up disabling the switch ports or causing a spanning-tree loop. Switches send BPDUs to determine the switch topology. Properly configured switches will have the access ports set to portfast and bpduguard. This configuration will disable the ports in ...


3

iPerf or Tamosoft throughput test. As a primarily Mac shop I currently find TTT more convenient, as iPerf builds for Mac are somewhat limited to specific OS versions or "build it yourself". TTT is a straightforward (and cross-platform) download and run. ...but iPerf is by far the more commonly/widely accepted method among network professionals. Have used ...


3

I'm inclined to believe that it is your caps/non-caps on the bandwidth designations (i.e. -b 10M -l 32K -w 128K). I can't test it because we don't know what version you're running. Iperf does make a distinction between bits and bytes: -f, --format [kmKM] format to report: Kbits, Mbits, KBytes, MBytes Though, the sections you were modifying were ...


3

For metrics you can look in to the reports that NSS labs are publishing, they have pretty solid documentation on how they do firewall testing. You can also google for their reports, sometimes firewall vendors publish them free of charge on their own web page for promo purposes. As for what tool you need you can use the ones you have listed, but it boils ...


3

There is one particularity about iperf 2.0.x with UDP: Within the limits (CPU, NIC, UDP/IP stack and its buffers) of the sending system, iPerf will send traffic at the payload rate you specify with the -b parameter (if left out, iperf will default to 1Mbit/s). EDIT: D'oh! Only now I spotted that you are actually using iperf3. I'll leave these comments ...


3

“Inline” refers to PoE, not to the position of the tester. So this with this tester you can check cables doing power over Ethernet. You would still place the tester at the ends of the cable.


3

What you're looking for is a cable tester able to certify a cable with the entire test suite. The tests must include crosstalk and detailed frequency measurement. Basically, there are three classes of testers: just continuity and shorts - 5-100 € additionally wire map (proper pairings), overall length, possibly rough frequency response (cable class) - 200-...


2

You need to have the server in Receive mode (i.e. -r option). Try the below command syntax. ttcp -r -s -p 3333 -D Check out the ttcp man page for more details. Further reading In order to make this a viable setup, you need a sender and receiver. The sender effectively establishes all of the prameters the tcp session will be benchmarked on. Transmit ...


2

By far the best packet and traffic generator I have come across for Linux is PacketETH; You can use it via CLI or via GUI. It is for generating Ethernet frames but you can also specify higher protocols such as IPv4/6, and TCP/UDP etc. It's very powerful letting you customise pretty much all header options for protocols in layer 2, 3 and 4 (so Ethernet, ...


2

Since you are wanting to measure a layer 2 circuit, I'd like to shamelessly push some free software that I have been writing. It's still in beta but does exactly what you want based on the information in your question. Unlike nuttcp, iPerf, jPerf et al, Etherate runs directly over layer 2 designed specifically for Ethernet testing. Like the others a laptop ...


2

useful tool can help you to make good wireless survey is wifi analyzer on the android phones. its can work on both ranges 2.4 and 5 GHZ you can use it to figure out channel utility and it DPI and it can help in find the places of the APs as well on PC insider could be one of the best wireless survey tools


2

You may be confused about something. You application may create threads for execution on your PC, but routers switch packets one at a time, regardless of what came before, and routers have no expectation that anything is coming in the future. Each packet is handled as an individual packet to be switched. The router may not be able to handle the throughput ...


2

in terms of server and client communications . based on stream or traffic traffic going from the server to the clients called downstream , and from clients to server called upstream . based on device connections client is up linked to server and server is down linked to clients


2

While passing downlink traffic (from the Access Point (AP)) to client-nodes, the AP schedules the packets from the packet-queues in the appropriate way and also does not face any contention on the medium. On the uplink however (from the client-nodes to the AP), the client-nodes contend for the medium to send the packet. This creates a delay. This delay in ...


2

Check the manual/datasheets - both the switch and the transceiver should state what they're compatible with. If you're using a range of different optics it makes a lot of sense to maintain a compatibility table. Check the log - the transceiver should be logged as incompatible if it is. A loopback test makes sure the link can come up - don't do it without M/R/...


2

A cable tester of that type injects a pulse into the cable and analyzes the time it takes to reflect back. That tester can't really test/certify a cable deployment (you'd need attenuation, NEXT/FEXT, ...) but it does show a problem - the short lengths you've got indicate a "bump" in the cable that reflects enough energy to trigger the analyzer. Most likely, ...


2

I offer another interpretation: 4 wire cable for 100Mbit/s. This is basically the same as zac67's answer "Either it's a bad LSA contact, a bad panel insert or a damaged cable.", but probably the situation is intentional, not accidental. It is compelling that it's exactly pairs 1/2 and 3/6 that are 20m long, while the other pairs are just shown with the ...


2

It took about 10 seconds to search the Internet to find this: To configure NAT translation in regular testing, all you have to do is open “Network Neighbourhood,”(In case you need a quick recap of the BreakingPoint components, you can find them here) click on the “NAT” field in the IPV4 STATIC HOSTS bucket as shown below and……. that’s it! ...


2

That's how iperf3.x works. The "client" wants to establish a control channel to the "server" before any UDP transfer is started. That's why you can observe some TCP before the UDP transfer starts. I haven't checked, but I believe that there is also a separate control channel connection when running TCP tests. In contrast, iPerf 1.7 and 2....


1

From what I know there are no upper limits in the 802.11 protocol. There are software limits in some of the AP's I've worked with. Aerohive usually have 100 concurrent stations on most AP's. The way wifi works is that only one client can talk to the AP at any given time. So the more stations, less time to talk for every each one of them. My guess is that ...


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