ubuntu ssh tunnel

tunneling on Linux 

First of all, let me show you about the basic package of data that we transmit among computers, see this :

what we can see is header is basic information about the package, then payload is data that we want to communicate to others. 

Firewall 

its use to make internet security, admin setup their network securely by allowing some port only to communicate. Firewall is terms on logic, its not hardware.

Router 

as you know, maybe router is identify as hardware such as wrt45g, belkin, mifi for mobile internet. Actually router can use to make firewall, its route the traffic to certain host or discard it.

Nat / masquerade

Network Address Translator (NAT) is also can be used to make firewall by re-translating IP from public to private of reverse. 

Secure Tunnel Proxy 

people use tunneling to make proxy tunnel for anonymous browsing. Generally, they build proxy server website to serve or as free proxy software for public. There are some tunneling in Linux, you may build http tunnel, http header tunnel, ssh tunnel, ack tunnel, dns tunnel or hidding data in IP.

on this section, i want to share about : 

how to build ssh tunnel

ssh tunnel is used when you are behind a network that only allow on port ssh (e.g 22 or other port).

first step : 

ssh -L 2323:hostC:123 username_B@hostB 

it usually use to make secure proxy browsing or browse with proxy, if you want, you just need to install squid proxy on hostC so that you can browse privately.

second step : 

go to your web browser, (e.g firefox), go to edit -> preference -> network -> setting -> manual configuration, then fill it by localhost, port 2323.

if you want to use DNS from hostC, just setup your firefox as below : 

if you use -R option (reserve tunnel), you need to set "GatewayPorts yes" on server side.

next, you can try to make ssh socks proxy

..show all:.

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tunneling on Linux 

First of all, let me show you about the basic package of data that we transmit among computers, see this :

what we can see is header is basic information about the package, then payload is data that we want to communicate to others. 

Firewall 

its use to make internet security, admin setup their network securely by allowing some port only to communicate. Firewall is terms on logic, its not hardware.

Router 

as you know, maybe router is identify as hardware such as wrt45g, belkin, mifi for mobile internet. Actually router can use to make firewall, its route the traffic to certain host or discard it.

Nat / masquerade

Network Address Translator (NAT) is also can be used to make firewall by re-translating IP from public to private of reverse. 

Secure Tunnel Proxy 

people use tunneling to make proxy tunnel for anonymous browsing. Generally, they build proxy server website to serve or as free proxy software for public. There are some tunneling in Linux, you may build http tunnel, http header tunnel, ssh tunnel, ack tunnel, dns tunnel or hidding data in IP.

on this section, i want to share about : 

how to build ssh tunnel

ssh tunnel is used when you are behind a network that only allow on port ssh (e.g 22 or other port).

first step : 

ssh -L 2323:hostC:123 username_B@hostB 

it usually use to make secure proxy browsing or browse with proxy, if you want, you just need to install squid proxy on hostC so that you can browse privately.

second step : 

go to your web browser, (e.g firefox), go to edit -> preference -> network -> setting -> manual configuration, then fill it by localhost, port 2323.

if you want to use DNS from hostC, just setup your firefox as below : 

if you use -R option (reserve tunnel), you need to set "GatewayPorts yes" on server side.

next, you can try to make ssh socks proxy