I'm beginning to write a custom RTP implementation and want to test its resilience to UDP traffic. I've searched on the web and all the links I can find are for analysing actual traffic, not generating it or messing it up.
Does anyone know of any software (preferably free software) that will, for example, take actual UDP traffic and drop packets, duplicate some and make some arrive late/out of sequence?
Does udp use Packet Sequence Number?
View 2 Replies View RelatedI am simulating a TCP/FTP to TCP/FTP network and trying to monitor the packet loss.
I am able to monitor and graph data regarding the TCPSinks' bytes received, but I can't monitor packet loss.
Why is it that the TCPSink Agent has a variable for bytes (bytes_) but not one for monitoring packet loss?
Do I have to monitor the packet loss from the queue? If so, how do I write code for this?
Below is part of the code for monitoring bytes received from sinks if anyone was interested.
I am just starting my adventure into Ubuntu. After installing and configuring Shrew Soft in Ubuntu 10.04 64Bit, I am having some serious packet loss issues. The LAN is wireless, however the only packet loss I experience is over the tunnels. I have tried different algorithms, and it seems as I fiddle with the MTU client side, it clears a bit, but the best I have managed is 23% loss average.
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I adjusted my routes to use my ppp1 (VPN) connection for almost all browsing. Have I misconfigured something.? Some more background information: My VPN is about halfway around the world from where I am / my PPPoE connection. I've already changed my DNS servers in /etc/resolv.conf to Google's 8.8.8.8.I get around 2 kBps on Ubuntu and 50 kBps on Windows using the same VPN. =/
I try to setup a locale network between 10 (Web) Servers (openSuse 11.2), each Server is connected to the internet (eth0) which works fine on all servers.
A 2nd NIC eth1 (1GBit rtl-8169) on each Server is connect to a Switch and should function as a LAN. I installed/configured the 2nd NIC with yast, and than added a route for the local network (192.168.20.0) to use eth1. So far every thing works (ssh for example), but I have a packet loss of 10%-60% (ping) on the local network, and I cant find the reason for the packet loss. I already installed a Debian Lenny on 2 Servers (just to test) but I have the same problem on Debian.
No firewall or any other application is in the way. With tcpdump I could figure out that the packages are send but never show up on the destination server.
I put some more information about how I configured the LAN below. I have not done this my first time and from my experience if something is wrong with the network configuration (wrong routing, firewall in the way, etc.) this usually leads to a packet loss of 100% or the destination is simply not reachable.
The 2nd NIC is installed with either yast on suse , or by editing /etc/network/interfaces on debian. The Kernel module rtl8169 is loaded.
They are configured with the following values:
Route is added by:
Output example. of ifconfig :
Output of route (same on all servers):
Output of ping:
I got a new X201 which is running Ubuntu 10.04. While at home, everything is fine, at work, I encounter some issues with wireless. the signal cuts in and out repeatedly.Here's the output of ping. I set it to ping a server every 90 seconds, 10 times. So this is a snapshot of 15 minutes of network activity...
Code:
PING (REDACTED) bytes of data.
64 bytes from (REDACTED): icmp_seq=1 ttl=252 time=1.50 ms
64 bytes from (REDACTED): icmp_seq=2 ttl=252 time=2.13 ms
64 bytes from (REDACTED): icmp_seq=3 ttl=252 time=1.38 ms
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Also I tried this (from a 2 year old thread which was most relevant solution I could find):
Code:
Changing AVAHI_DAEMON_DETECT_LOCAL=1 to AVAHI_DAEMON_DETECT_LOCAL=0 in /etc/default/avahi-daemon has got rid of the irritating pop-up. Basically, every 5 minutes or so, for a solid 60 seconds or so I get no signal. I've tried updating the kernel, and doing apt-get remove avant-daemon, but still have problems.
I have a following configuration: 4 PCs (say, A, B, C and D), running Ubuntu or Debian, interconnected using a gigabit switch, which is connected to the Internet. Two machines (say, A and B) also have a direct private connection between them (provided by another pair of NICs).
Now, when I test the connection performance with iperf, the results vary. The private connection between A and B performs well - about 930Mbps using iperf's UDP test. Between C and D it is about 800Mbps which I find tolerable. Packet loss when running these tests is negligible.
However, when I run iperf between any of {A,B} and {C,D}, the performance significantly drops as there is a huge number of lost packets.
For example, here is the result of testing between A and C:
Why is there such a large number of packets which are generated, but lost somewhere?
A<->B private link works fine, so system level parameters on both A and B are correct. Furthermore, C<->D works ok, so I guess I shouldn't blame the switch.
Is there a per-NIC configuration that I should check or it smells like a hw problem? Problematic NICs on both A and B are of the same type - Allied Telesyn AT2916T.
I am running Slackware 13.0 on a old dell dimension 4500. The install went fine. sound worked, graphics where good. Everything was going perfect. until i worked on wireless.i have a realtek rtl8185 wireless chipset card. I got the wireless. Linux wireless driver. It worked on both Mint 5.0 and backtrack 4.0.so I untar the file. cd to the dir and type make then make install and reboot. like I have always done.
I was having to fight with wpa_gui and finally got it working but then it would go in and out on the connect and disconnect feature. so I tried using iwconfig. did not get muc luck with that either so i installed wicd and finally got a ip address after fighting with it would give me in a ping like 75% packet loss. so I read a lot of post and try to find stuff before I post. and while reading I learned that you guys normally ask for info on the hardware and software so here you go. but I will say first that I read about adjusting the mtu to fix packet loss, I showed some of the changes I made in it around the pings I know it is a mess I am sorry I tried to make it readable. if you need more information let me know. I cant get online using a web browser or if I can only for one or two pages. any help would be great. thank you.
Code:
bash-3.1# ifconfig
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
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I'm using kubuntu 9.10 desktop edition as a server and I set the IP statically, what happens is that when I ping it from another machine on the same network, I get intermittent packet loss (up to 80% and sometimes even higher). When I ping any other machine on the local network everything's fine with 0% packet loss. Packets go directly through switch, no router or anything in between.
I suspected wiring issues, but that doesn't seem to be the problem after I changed the wiring. I was connected to wireless and suspected that but no go either. Same thing when I turn wired. I just changed the ethernet card suspecting drivers but that's no good either. Iptables is a cleanslate installation, it's totally empty.
Just want to know if my connection will be good for voip like skype...
View 1 Replies View RelatedI have ubuntu lucid running on Dell 230 PC, linksys WPN600 N wireless PCI network card connecting to a Cisco E3000 dual channel router.
Kernel: 2.6.32-33-generic
Installed Ralink driver v2.4.0.0
iwconfig shows that the bit rate is 130Mb/s and link quality is 98/100. I'm using the wcid network manager instead of defaul gnome one. I'm getting lots of packet loss and performance is very bad. The connection is practically unusable. I've tried installing the compat wireless backport package but that did not work at all.
I am running Linux Mint Isadora 9 and recently installed a wireless USB adapter. After installing RT3070 drivers for my RT2070 card I got everything working and life was good. Now, all of the sudden I am having a world of problems connecting to the internet. I can connect to my AP fine, but I cannot access the internet. If I attempt to ping my AP by IP address I get severe packet loss. I cannot ping my AP by url [URL] at all so Im guessing there are some DNS issues as well.
Code:
poe jk # lsusb
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 003: ID 046d:c045 Logitech, Inc. Optical Mouse
Bus 003 Device 002: ID 413c:2005 Dell Computer Corp. RT7D50 Keyboard
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I am running Redhat linux 8.0 with 2.4.22 kernel. I am using this server for traffic shaping my static ip clients using tc. There are about 250 clients and I am running mrtg to monitor traffic via cronjobs each 5 minutes. When mrtg run I see too much packets loss in my network. What could be the problem in my server?
RAM is 1gb and processor is Intel Pentium D 2.66GHz.
I have problems with my network speed when i ping my proxy server I end up getting a high packet loss generally more than 30%.I have tried to use various network monitoring softwares like etherape, wireshark, tcpdump but I am not able to get to the bottom of the problem.basically I am trying to find out where the lost packets are going.
View 7 Replies View RelatedI have linux workstation. All users home directories are NFS mounts.
Since I am facing packet loss issue users are unable to login to the workstation.
I found the packet loss using mtr from workstation to filer.
Matt's traceroute [v0.54]
Hostname
What are the things I have to check to resolve this packet loss.
Following is the ethtool out put of the workstation
Settings for eth0:
i made a video and i wanted to put it on my myspace(video upload) and it justs fade to grey and becomes unresponive. that it goes back to normal but no progress. so then i tried going to image shack and uploading a picture. can't do that either. tried mediafire, videos, vimeo, nothing.
so i tried on my desktop(desktop running 9.10 32 bit. laptop(the first one i tried) running 9.10 64 bit. it didn't work on that either. i know it's not my isp because it works on my ps3(no ubuntu). not my firewall and tried without without my router. didn't work either. i tried upgrading flash on both of them and on my desktop i can upload some pictures to imageshack now. nothing else though. i have tried using both firefox and opera.
i pinged yahoo and this is what i got:
6 packets transmitted, 6 received, 0% packet loss, time 5007ms
rtt min/avg/max/mdev = 72.732/73.437/75.024/0.761 ms
I am recently trying to get a steady wireless connection running. I am currently using the default settings/driver Fedora 13 is stocked with. As my internet browsing is somewhat up and down in load times, I decided to check in a video game which is generally a good test for me. haha I am harshly spiking and cannot find the source of my problem so my guess is a driver issue.
lspci | grep Network:
Code:
Code:
It is is seemingly right, my Windows 7 harddrive works just fine, this is just one last of the few issues I'm having from fully formatting my winblows HD to use as Linux storage.
I cannot find any native AR5008 Linux Drivers for my card and it has been a frustrating day. I guess I'm not cut to be a network analyst just yet.
System specs:
ASUS P5Q SE/R
Intel Core 2 Quad Q9550
4GB DDR2 667
Gigabyte GTX465 1G
TP LINK TL-WN851N Wireless card
I have 3 Dell Precision M4400 machines. After getting updates yesterday or today, I get random network dropouts like crazy, on wired or wireless. On one machine I was able to turn off ipv6 in grub and reboot, and it works now. However on the other 2 machines, still have the same problems. All 3 are running 9.10 64 bit. Is there a way I can back out the updates so the network works again? Anyone else see this behavior after updates today?
View 2 Replies View RelatedI',m executing ping, but it didn't work, in order to find the mistake in my network I would like to know how to see the errors:
Code:
18 packets transmitted, 0 received, +12 errors, 100% packet loss, time 17038ms, pipe 4 I want to see this +12 errors. Could I do that?
I have an academic simulator software and I want to visualize its output at the same time the simulation is happening. However I want to separate visualization and simulation modules. The simulation data will be held in an array of a size around 0.5M and will be read only to visualization software (but updated regularly by simulator).
- In past I have used shared memory to share small variables among two applications.
- TCP/IP adds the option of having the simulator and visualization applications on separate machines but the implementation will be more difficult.
- I have also thought about an abstraction layer which allows to replace the communication/interconnection layer with other methods later (file/network/shared memory/pipe).
I am trying to generate sequence of number in the order of :
1
2
3
4
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How can we build a packet using C?we have a structure called sockaddr_in which is use to for IPv4,so that we can define address,port and etc in this way:
Code:
struct sockaddr_in sock;
sock.sin_family=AF_INET;
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I tried googling around but i cant find anything related to this: everyone seems just interested in random numbers, so when it comes to random letters there is a lack of informations. However, i am trying to figure out a wait to get a random letters string that matches a simple rule: it must be a sequence of consonant+vowel. So for example, these are some 6 letters strings i would like to obtain: wolupa, tafoke, zewevu, cupimo.
View 3 Replies View RelatedI have to write a code that converts a sequence of 1's and 0's(block) into their equivalent hexa number and copying to another array(byte). but this sequence is not always of length 8 and you are required to send strlen(sequence)%8 bits back into the string. So i've written down this code and it works well with the sample input but fails in the real program.
Code:
int Convert_encode( char * block,unsigned char * byte)
{
int len,iter,i,j,k,sum;
char * temp=(char *)malloc(4*sizeof(char));
len=strlen(block)/8;
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I am faced with the following problem; I need to update all fields of type datetime without ... with the following sort data:01-01-2010 12:10:30.256 - this is just an example.these fields are restricted with a unique constrained. My question is how can I generate the above sort data, especially the last three numbers with leading point. After that how can I update a table with existing data with this newly generated data so that the fields really do carry unique data.As you probably can read out of my question, I read through the help in pgAdmin and came as far as generating date, maybe datetime but not the .123 number. And a little insert script I found in the help, that I modified as UPDATE resulted in updating only the last generated data in all required fields.
View 7 Replies View RelatedI want to create my own packet for aodv so how can i do? from where i should start?
View 2 Replies View RelatedI want to develop program to put (tunnel) sniffed packets into another packet, i already have sniffer code to capture packet, can some one give me use full site or simple code to do that.
View 3 Replies View RelatedI am the new user to ns-2. I would like to know is it possible to send the keys or some value as the packet data (content of the packet) in ns-2 (for wireless environment).
View 1 Replies View RelatedI got a problem with my CentOS server. Somebody told me OpenVPN Requires different changes inside my firewall settings. That could be the problem why openvpn wont load..I receive this error on my CentOS panel when im trying to connect into the centos openvpn (with my winxp pc):
Thu Sep 17 20:31:36 2009 TLS Error: incoming packet authentication failed from 84.xx.62.122:2622
Thu Sep 17 20:31:38 2009 Authenticate/Decrypt packet error: packet HMAC authentication failed
Thu Sep 17 20:31:38 2009 TLS Error: incoming packet authentication failed from 84.xx.62.122:2622
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