April 2, 2013
no ssh via mobile in france (SFR, Orange)
узнал сегодня, что мобильные операторы во франции блокируют ssh, vpn, даже smpp. короче, все, кроме http/s. это хуже, чем даже в китае с их файрволом!
а китайцы ведь разрешают vpn и ssh!
а китайцы ведь разрешают vpn и ssh!
Labels: block, china, firewall, france, mobile operators, network, shit, ssh, vpn
March 11, 2012
Which WiFi channels overlap: diagram
August 3, 2010
Default socket option values for Java connections, Ubuntu 10.04
Tested on local connection. Note the relatively large buffer sizes.
Socket=Socket[addr=/127.0.0.1,port=46179,localport=33333]
SEND_BUF=25350
RECV_BUF=43760
REUSE_ADDR=true
SO_TIMEOUT=0
SO_LINGER=-1
OOB_ININE=false
TCP_NODELAY=false
TRAFFIC_CLASS=0
December 28, 2009
tele2 gprs: real ip! and some interesting udp stuff
The Tele2 cell operator provides a real (not from the private network) ip for phone, so it's possible to exchange UDP (just tested it) to WAN. The problem is that each time the phone enables GPRS it has different ip, even from different B class networks ;-)
By the way, I used the simple java udp echo server and simple midlet to test udp interconnection and latency.
By the way, I used the simple java udp echo server and simple midlet to test udp interconnection and latency.
June 28, 2009
[solaris] LSOF substitute
lsof sometimes cannot work OK for TCP information after kernel updates on solaris (10, both sparc and x86). The reason is that kernel data scructures changes. So if you cannot recompile, i recommend in case of port-PID mapping to use such a simple script: http://www.unix.ms/pcp/. Tried it, works ok.
PS Mac users, try it plz?
PPS: Local copy: pcp.sh
PS Mac users, try it plz?
PPS: Local copy: pcp.sh
Labels: administering, lsof, network, solaris
