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13

Details vary but basically it goes something like. The two peers both open a UDP socket bound to a random local port The two peers both contact a server on the internet. This server responds and tells them what IP and port their packet was received from. Since the server is on the Internet the IP/port seen by the server is the external IP and port The two ...


9

You can certainly do this with Wireshark. In the menu choose Statistics > Endpoints and you will see a window like this: You might need to copy and paste into Excel to sum the bytes per AS, or use some awk/python one-liner. If the columns marked AS Number and AS Organization are blank throughout, you need to configure the database for looking these up. ...


4

The Linux command nping has a --df flag for setting the Don't Fragment bit in the flags; it also can generate TCP and UDP traffic, not just ICMP. Will that help?


4

It's all depends upon network connectivity bandwidth and server NIC card bandwidth threshold . If excess of traffic come on physical links then packets are queued resulting in congestion of physical links leads to packet drops and applications will experience latency in accessing . Traffic is even get queued when server nic cards exceed its handling ...


3

If the bandwidth limit is a physical link capacity, excess traffic is dropped. A very small amount might get queued and dequeued again when the bandwidth has decreased below the physical limit, but anything seriously exceeding the link capacity cannot be forwarded and is lost. If it's a software limit, the exact handling depends on the configuration and the ...


3

The bandwidth command sets the reported bandwidth and is used for metric calculation only. It does not affect the actual interface bandwidth. If you want to limit bandwidth, you will need to implement traffic shaping/policing.


3

We would like to keep an eye on browsing traffic on LAN 192.168.2.0/24, because we don't want guests to visit wrong websites. Instead of "keeping an eye" on specific traffic you should simply block unwanted traffic. Separate guest subnet from management subnet by firewall. Allow guest subnet access to Internet but not to management network. Allow ...


3

Junos-host zone can be used to add an additional check for traffic destined to SRX. If you don't configure any security policy to-zone junos-host, the traffic/packet will be validated based on host-inbound-traffic configured under security zones. If you configure security policy to-zone junos-host, that policy check will be done additionaly to host-...


3

The most common mistake made when using netem to emulate network delay is to not increase the packet limit. You didn't. Therefore you tail drop a lot of packets and tcp cannot build a queue long enough to emulate the path. try limit 1000000 or more. Monitor your netem stats to see if you drop any packets. Plug: we use (bufferbloat project) flent.org's test ...


2

Client A <--> Access Point C <--> Client B A switch is not necessary. It might be helpful to think of the AP as a wireless bridge.


2

I've got ~180 KB after one hour with an idle connection - so, depending on the exact OpenVPN version and configuration, 20 MB/day seem about right. You'll need to monitor the connection on the gateway itself to find out what exactly this traffic is. You should be able to run tcpdump on OpenWRT - however, consumer-grade devices are off-topic here.


2

I think, this is a somewhat brooder question to answer. There are many option you can implement. Firewall Implementation Network Monitoring System Implementation Proxy Server Implementation We have no idea about size of your network, and but generally real time monitoring on each user is not a good idea and it will not be a possible if you have lot of ...


2

You can limit the size of the captured frames to just the header. That will drastically reduce the size of your capture files. From ask.wireshark.org: From the Capture menu select "Options..." (or press Ctrl + K), and then click on the Snaplen column item for the interface you which to set the capture length on. This gives you an edit\spin box which ...


2

As commonly used, a border link is the point to point network between an organization and other, external networks. The most common example is the link between a organization's network and an Internet service provider. Backbone links are usually internal point to point links that make up the "core" of a network topology. The authors are saying that the ...


2

Cisco CSR does not have support for SR on AWS, see here for AWS requirements/support. There is no support for SR as in SR-IOV "single root virtualization", there is support for SR as in segment routing. ALso keep in mind that AWS EC2 performance varies by instance type. The AWS Marketplace page for the CSR 1000v lists lists 4 instance types. Though not ...


1

It sounds like what you really want is a DDOS detection & automation system. Wanguard is probably the most popular small-scale solution. In your environment, you can use it to detect DDOS with Netflow/sFlow or a traffic mirror. It can then send alerts and generate BGP routes for black-holing, depending on how you configure it. There are other software ...


1

Per Decrypting TLS Browser Traffic With Wireshark – The Easy Way!, As people have started to embrace forward secrecy this broke, as having the private key is no longer enough derive the actual session key used to decrypt the data...Firefox and Chrome both support logging the symmetric session key used to encrypt TLS traffic to a file. You can then point ...


1

Just providing 2 egress policies won't suffice. Traffic to unknown target networks has to follow the default route. But, there is only 1 default route per system/FGT (for obvious reasons). To match a (static) route the FGT only looks at the destination IP address. In your case, this is not enough because you want traffic from different sources to follow ...


1

The easiest way is to split traffic by firewall policy - just the one WAN interface for one set of policies and the other interface for another set. If you want to split traffic to different external IP addresses on the same interface you can define an IP Pool (with possibly just a single address) and use that in a policy instead of Use Outgoing Interface ...


1

Ping (icmp) by default is not allowed through a Cisco ASA and you need to create a rule on the outside->in to allow icmp to respond. Cisco ASA is a statefull firewall except for ping.


1

The referenced paper is modelling the rate of traffic, trying to get it to behave like real traffic. As they say the "model provides a simple and accurate network traffic generator that matches statistical properties of real-life IP networks." They're not trying to model the mix of different kinds of packets.


1

I believe you are misinterpreting this statement: The router shaper applies only to traffic on the data plane forwarding CPU, and it applies only to egress traffic leaving the data plane. It doesn’t apply to traffic only traversing the Multi-Gigabit Fabric (MGF). to infer that there are three "categories" of packets: Which traffic belongs to ...


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