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Offline regentag

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ping
« on: December 25, 2009, 03:24:45 AM »
ping
///rā'gən·täg

Offline KMA

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Re: ping
« Reply #1 on: December 25, 2009, 06:05:37 AM »

Offline regentag

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Re: ping
« Reply #2 on: December 25, 2009, 06:26:53 AM »
Curly?
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Offline KMA

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Offline KMA

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Re: ping
« Reply #5 on: April 18, 2010, 02:14:54 AM »

Lost Locations









« Last Edit: April 18, 2010, 02:25:33 AM by KMA »

Offline Rebel

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Re: ping
« Reply #6 on: April 18, 2010, 08:56:12 PM »


Looks like home to me.

“The conscious and intelligent manipulation of the organized habits and opinions of the masses is an important element in democratic society. Those who manipulate this unseen mechanism of society constitute an invisible government which is the true ruling power of our country." - Edward Bernays

Offline KMA

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Re: ping
« Reply #7 on: April 18, 2010, 11:54:55 PM »


Looks like home to me.



If you're a fan of Lost this is Eko's Church.

Offline Rebel

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Re: ping
« Reply #8 on: April 20, 2010, 08:22:04 PM »
I gave up on Lost part way through the second season.

Looks like a good spot to have church to me though.
“The conscious and intelligent manipulation of the organized habits and opinions of the masses is an important element in democratic society. Those who manipulate this unseen mechanism of society constitute an invisible government which is the true ruling power of our country." - Edward Bernays

Offline regentag

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Re: ping
« Reply #9 on: May 09, 2010, 03:52:00 AM »
One man's lost is another man's home is his castle.
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Offline KMA

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Re: ping
« Reply #10 on: May 16, 2010, 02:02:32 AM »





 :drool: :occasion14:

Offline boo5ted

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Re: ping
« Reply #11 on: May 16, 2010, 04:25:25 AM »



ping
From Wikipedia, the free encyclopedia
For other uses, see Ping (disambiguation).   This article needs additional citations for verification.
Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (July 2008)


Ping is a computer network administration utility used to test whether a particular host is reachable across an Internet Protocol (IP) network and to measure the round-trip time for packets sent from the local host to a destination computer, including the local host's own interfaces.

Occasionally Packet InterNet Groper is suggested as a backronym, but the original author of Ping says that it is based on the sound of a sonar return.[1]

Ping operates by sending Internet Control Message Protocol (ICMP) echo request packets to the target host and waits for an ICMP response, sometimes casually called a pong. In the process it measures the round-trip time[1] and records any packet loss. The results of the test are printed in form of a statistical summary of the response packets received, including the minimum, maximum, and the mean round-trip times, and sometimes the standard deviation of the mean.

The use of the ping utility is usually described as pinging a host computer. Ping has various command line options depending on the host operating system that enable special operational modes, such as to specify the packet size used as the probe, automatic repeated operation for sending a specified count of probes, time stamping options, or to perform a ping flood. Flood pinging may be abused as a simple form of denial-of-service attack, in which the attacker overwhelms the victim with ICMP echo request packets.Contents [hide]
1 History
2 ICMP packet
3 Example ping tests
3.1 Linux
3.2 Windows
3.3 Mac
4 Message format
4.1 Echo request
4.2 Echo reply
4.3 Other replies
5 Payload
6 In gaming
7 In common usage
8 See also
9 References
10 External links

[edit]
History
 
A server denying a ping request because of the request's size.

Mike Muuss wrote the program in December 1983, as a tool to troubleshoot problems in an IP network. He named it after the pulses of sound made by a sonar, since its operation is analogous to active sonar in submarines, in which an operator issues a pulse of sound toward the target, which then bounces from the target and is received by the operator.[1][2]

The usefulness of ping in assisting the diagnosis of Internet connectivity issues was impaired starting in 2003, when a number of Internet service providers began filtering out ICMP Type 8 (ICMP Echo Request) messages at their network boundaries.[citation needed] This was partly due to the increasing use of ping for target reconnaissance, for example by Internet worms such as Welchia that flood the Internet with ping requests in order to locate new computers to infect. Not only did the availability of ping responses leak information to an attacker, it added to the overall load on networks, causing problems for routers across the Internet.[citation needed]

Although RFC 1122 prescribes that any host must accept an echo-request and issue an echo-reply in return, this is supposedly a security risk.[citation needed] Thus, hosts that no longer follow this standard are frequent on the public Internet (eg: www.microsoft.com).[citation needed]
[edit]
ICMP packet
ICMP packet    Bit 0 - 7   Bit 8 - 15   Bit 16 - 23   Bit 24 - 31
IP Header
(160 bits OR 20 Bytes)   Version/IHL   Type of service   Length
Identification   flags and offset
Time To Live (TTL)   Protocol   Checksum
Source IP address
Destination IP address
ICMP Payload
(64+ bits OR 8+ Bytes)   Type of message   Code   Checksum
Quench
Data (optional)


Generic composition of an ICMP packet[3]
Header (in blue):
Protocol set to 1 and Type of Service set to 0.
Payload (in red):
Type of ICMP message (8 bits)
Code (8 bits)
Checksum (16 bits), calculated with the ICMP part of the packet (the header is not used)
The ICMP 'Quench' (32 bits) field, which in this case (ICMP echo request and replies), will be composed of identifier (16 bits) and sequence number (16 bits).
Data load for the different kind of answers (Can be an arbitrary length, left to implementation detail. However must be less than the maximum MTU of the network[citation needed]).
Data Transportation

Note that ICMP (and therefore Ping) resides on the Network layer (level 3) of the OSI (Open Systems Interconnection) model. This is the same layer as IP (Internet Protocol). Consequently, Ping does not use a port for communication.
[edit]
Example ping tests
[edit]
Linux

The following is a sample output of pinging en.wikipedia.org under Linux with the iputils version of ping:
admin@localhost# ping en.wikipedia.org
PING rr.pmtpa.wikimedia.org (66.230.200.100) 56(84) bytes of data.
64 bytes from rr.pmtpa.wikimedia.org (66.230.200.100): icmp_seq=1 ttl=52 time=87.7 ms
64 bytes from rr.pmtpa.wikimedia.org (66.230.200.100): icmp_seq=2 ttl=52 time=95.6 ms
64 bytes from rr.pmtpa.wikimedia.org (66.230.200.100): icmp_seq=3 ttl=52 time=85.4 ms
64 bytes from rr.pmtpa.wikimedia.org (66.230.200.100): icmp_seq=4 ttl=52 time=95.8 ms
64 bytes from rr.pmtpa.wikimedia.org (66.230.200.100): icmp_seq=5 ttl=52 time=87.0 ms
64 bytes from rr.pmtpa.wikimedia.org (66.230.200.100): icmp_seq=6 ttl=52 time=97.6 ms

--- rr.pmtpa.wikimedia.org ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 8998ms
rtt min/avg/max/mdev = 78.162/89.213/97.695/6.836 ms

This output shows that en.wikipedia.org is a DNS CNAME record for rr.pmtpa.wikimedia.org which then resolves to 66.230.200.100.

The output then shows the results of making 10 pings to 66.230.200.100 with the results summarized at the end. (To stop the program in Linux or Windows, press Ctrl+C.)
shortest round trip time was 78.162 milliseconds
average round trip time was 89.213 milliseconds
maximum round trip time was 97.695 milliseconds
Standard deviation of the round-trip time was 6.836 milliseconds

While a ping session is running, under some Linux systems, you can get the overall status of the session without quitting by sending the Ctrl+\ key combination. This will give you a summary similar to the following.
6/6 packets, 0% loss, min/avg/ewma/max = 15.304/23.188/20.446/53.673 ms
[edit]
Windows

The following is a sample output of pinging en.wikipedia.org under Windows (Windows 7 used in the following example) from within the Command Prompt:
Pinging rr.pmtpa.wikimedia.org [208.80.152.2] with 32 bytes of data:
Reply from 208.80.152.2: bytes=32 time=80ms TTL=53
Reply from 208.80.152.2: bytes=32 time=81ms TTL=53
Reply from 208.80.152.2: bytes=32 time=84ms TTL=53
Reply from 208.80.152.2: bytes=32 time=84ms TTL=53

Ping statistics for 208.80.152.2:
   Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
   Minimum = 80ms, Maximum = 84ms, Average = 82ms

Windows appears not to inform the user about duplicated return packets.

While a ping session is running you can get the overall status of the session without quitting by sending the Ctrl+Break key combination.
[edit]
Mac

The following is a sample output of pinging en.wikipedia.org under Mac OS X Leopard using the Terminal:
Macintosh:~ user$ ping -c 10 en.wikipedia.org
PING rr.knams.wikimedia.org (91.198.174.2): 56 data bytes
64 bytes from 91.198.174.2: icmp_seq=0 ttl=53 time=40.019 ms
64 bytes from 91.198.174.2: icmp_seq=1 ttl=53 time=47.502 ms
64 bytes from 91.198.174.2: icmp_seq=2 ttl=53 time=43.208 ms
64 bytes from 91.198.174.2: icmp_seq=3 ttl=53 time=50.851 ms
64 bytes from 91.198.174.2: icmp_seq=4 ttl=53 time=46.556 ms
64 bytes from 91.198.174.2: icmp_seq=5 ttl=53 time=42.180 ms
64 bytes from 91.198.174.2: icmp_seq=6 ttl=53 time=49.853 ms
64 bytes from 91.198.174.2: icmp_seq=7 ttl=53 time=45.556 ms
64 bytes from 91.198.174.2: icmp_seq=8 ttl=53 time=41.186 ms
64 bytes from 91.198.174.2: icmp_seq=9 ttl=53 time=48.836 ms

--- rr.knams.wikimedia.org ping statistics ---
10 packets transmitted, 10 packets received, 0% packet loss
round-trip min/avg/max/stddev = 40.019/45.575/50.851/3.588 ms

While a ping session is running you can get the overall status of the session without quitting by sending the Ctrl+t key combination. This will give you a summary similar to the following.
load: 0.37  cmd: ping 1748 running 0.01u 0.07s
255/255 packets received (100%) 18.827 min / 19.975 avg / 29.200 max
[edit]
Message format
[edit]
Echo request

The echo request is an ICMP message whose data is expected to be received back in an echo reply ("ping"). The host must respond to all echo requests with an echo reply containing the exact data received in the request message.00   01   02   03   04   05   06   07   08   09   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28   29   30   31
Type = 8   Code = 0   Header Checksum
Identifier   Sequence Number
Data :::

The Identifier and Sequence Number can be used by the client to match the reply with the request that caused the reply. In practice, most Linux systems use a unique identifier for every ping process, and sequence number is an increasing number within that process. Windows uses a fixed identifier, which varies between Windows versions, and a sequence number that is only reset at boot time.
The data received by the Echo Request must be entirely included in the Echo Reply.
[edit]
Echo reply

The echo reply is an ICMP message generated in response to an echo request, and is mandatory for all hosts and routers.00   01   02   03   04   05   06   07   08   09   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28   29   30   31
Type = 0   Code = 0   Header Checksum
Identifier   Sequence Number
Data :::

Type and code must be set to 0.
The identifier and sequence number can be used by the client to determine which echo requests are associated with the echo replies.
The data received in the echo request must be entirely included in the echo reply.
[edit]
Other replies

In case of error, destination host or intermediate router will send back an ICMP error message, i.e. host unreachable or TTL exceeded in transit. This messages additionally have first 8 bytes of original message (in this case header of ICMP echo request, including quench value), so ping utility can match it to originating query.[citation needed]
[edit]
Payload

The payload of the packet is generally filled with letters of the alphabet as this ASCII tcpdump shows
16:24:47.966461 IP (tos 0x0, ttl 128, id 15103, offset 0, flags [none],
proto: ICMP (1), length: 60) 192.168.146.22 > 192.168.144.5: ICMP echo request,
id 1, seq 38, length 40
      0x0000:  4500 003c 3aff 0000 8001 5c55 c0a8 9216  E..<:.....\U....
      0x0010:  c0a8 9005 0800 4d35 0001 0026 6162 6364  ......M5...&abcd
      0x0020:  6566 6768 696a 6b6c 6d6e 6f70 7172 7374  efghijklmnopqrst
      0x0030:  7576 7761 6263 6465 6667 6869            uvwabcdefghi

Some values of this payload indicates timestamp when message was sent to the network. This allows to compute round trip time in stateless manner - ping doesn't need to remember anywhere internally what and when packets was sent. When they return, all the data needed will be contained in the message. In case of no answer and no error message, most implementation of ping displays nothing, or periodically prints notification about timeout.[citation needed]
[edit]
In gaming
Main article: ping (video gaming)

In various network multi-player games, the server notes the time it requires for a game packet to reach a client and a response to be received. This round-trip time is usually reported as the player's 'ping'. It is used as an effective measurement of the player's latency, with lower ping times being desirable. Note that this style of ping typically does not use ICMP packets.
[edit]
In common usage

The term 'ping' is commonly used to indicate an effectively content-less message. For instance, a short or empty instant message, email, voice mail or "missed call" notification can be used to indicate availability, or anything else that can be conveyed with a single bit of information at a given time.[citation needed]

The term 'ping' is used as a verb, in the context of social or professional communication, meaning to simply probe for a response from someone whose presence, attention and interest are uncertain.[citation needed]

The term 'ping' can be used specifically to query if someone is available over Instant Messenger.[citation needed] The term is typically used in this fashion among computer professionals or other people who are familiar with the ping utility and its functionality.[citation needed]

Offline KMA

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Re: ping
« Reply #12 on: May 18, 2010, 01:00:04 AM »



 :D

Offline Ricky315

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Re: ping
« Reply #13 on: May 18, 2010, 07:18:07 AM »
what's up