[ACCEPTED]-Ping fails but http link works-windows
The site may be behind a firewall that blocks 2 ICMP requests (e.g., ping). HTTP requests 1 that your browser sends out goes over TCP/IP.
Ping sends an ICMP request package. The 8 webserver can choose to ignore it and not 7 respond, instead of responding with an ICMP 6 response.
The web brower uses HTTP, which 5 means it opens a TCP connection on port 4 80 by using a SYN/SYNACK/ACK exchange.
These 3 two processes are completely different and 2 independant, so you can enable/disable either 1 independantly.
The browser uses the TCP/IP protocol to 4 communicate with the server the HTTP requests, when 3 you use ping, it uses the ICMP protocol and 2 seems the server behind a firewall that 1 drops the ICMP Echo Requests.
A ping is essentially an "echo request" packet 10 sent over IMCP (a protocol). The correct 9 response to a ping is a handily "echo response" packet. However, if 8 you send an echo response packet, people 7 know you exist. Now, when you're running 6 a web server, this isn't a big deal, but 5 when you're running a standard desktop, you 4 don't want people knowing you exist. The 3 result is that many security-minded people 2 will disable ping responses by default, even 1 on server machines.
Public servers often don't respond to ping 11 requests. After all, people don't type ping 10 testsite.com before they open their browser, right? So 9 there's no real point to answer pings forthese 8 sites. On the other hand:
A few years ago, a 7 kid managed to simultaneously bring amazon.com 6 and a couple of other such big sites down 5 to thei knees during a couple of hours by 4 having a few hundreds machines bomb them 3 with loads of ping requests.
Since then, ping 2 has not been considered that much friendly 1 by admins.
It's not the browser. There could be a firewall 4 between you and the server that's blocking 3 the ping requests or the server simply may 2 not be responding to pings. It's a common 1 security measure.
Ping (also known as ICMP) and the http protocol 4 work completely differently and use different 3 ports. Different devices/firewalls along 2 the way may block ping but most allow http 1 through.
Ping packets, as others have stated, are 5 a different type of packet than 'HTML' packets 4 - Ping packets are ICMP/IP while HTML are TCP/IP. All 3 kinds of stuff in between you and the website 2 could choose to block the ICMP packets while 1 allowing TCP packets through.
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