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Questions tagged [packet]

A packet is one unit of binary data capable of being routed through a computer network.

This is a small amount of computer data sent over a network. Any time you receive data from the Internet, it comes to your computer in the form of many little packets.

Each packet contains:

  • A label which uniquely identifies it
  • The IP address of its origin and destination
  • A sequence number (for sorting)
  • A checksum (for error checking

The process of sending and receiving packets is known as "packet-switching." Packets from many different locations can be sent on the same lines and be sorted and directed to different routes by various computers along the way, the packets are then sorted by their sequence number once they reach their destination. It works a lot like the post office, except billions of packets are transferred each day, and most packets take less than a few seconds to reach their destination. Even FedEx same-day delivery can't compete with that.

Packet Definition. 2013. Packet Definition. [ONLINE] Available at: http://www.techterms.com/definition/packet. [Accessed 30 April 2013].

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JavaScript WebSockets with UDP?

I'm writing a JavaScript Application that has to receive a huge amount of data from other users. It is not important if some of this data gets lost. Is there some way of using JavaScript WebSockets with UDP instead of TCP?
user142019
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What is the mask in a WebSocket frame?

I am working on a websocket implementation and do not know what the sense of a mask is in a frame. Could somebody explain me what it does and why it is recommend? 0 1 2 3 0 1 2 3 4 5 6 7 8 9…
bodokaiser
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iPhone and WireShark

How can I sniff packets from my iPhone on my network? can someone give me some instructions? I tried Googling, but nothing teaches how to sniff iPhone packets、 I am on windows.
Strawberry
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Does TCP send a SYN/ACK on every packet or only on the first connection?

I have a TCP server that listens for an incoming client, then sends it one packet of data every second. I was wondering, does the SYN/ACK packet only get sent on initial connection, so it looks like this:
Daniel T.
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Capture incoming traffic in tcpdump

In tcpdump, how can I capture all incoming IP traffic destined to my machine? I don't care about my local traffic. Should I just say: tcpdump ip dst $MyIpAddress and not src net $myIpAddress/$myNetworkBytes ... or am I missing something?
Ricky Robinson
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When will a TCP network packet be fragmented at the application layer?

When will a TCP packet be fragmented at the application layer? When a TCP packet is sent from an application, will the recipient at the application layer ever receive the packet in two or more packets? If so, what conditions cause the packet to be…
zooropa
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Android VpnService to capture packets won't capture packets

I been searching for my answer for a couple of hours now and I can't figure it out. Please help. What I want to do is to use the VpnService in Android to grab network packets like the application tPacketCapture I started by using the ToyVpn sample…
Juan Acevedo
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How should I mark the end of a TCP packet?

In a client/server application were text data of varying length will be sent back and forth between the client and server, how should I mark the end of a packet that is being sent? For example, when the server is receiving packet data from a client…
Keith Maurino
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Sending UDP Packet in C#

I have a game server (WoW). I want my players to download my custom patches to the game. I've done a program that checks for update/downloading things. I want my program to send a packet to my game server if player have all my patches. I dont need…
DOminik
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Benefits of "Don't Fragment" on TCP Packets?

One of our customers is having trouble submitting data from our application (on their PC) to a server (different geographical location). When sending packets under 1100 bytes everything works fine, but above this we see TCP retransmitting the packet…
ta.speot.is
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Bluetooth Low Energy - updating a characteristic value repeatedly

Follow-Up question on Electrical Engineering Stackexchange I want to write the value of a Bluetooth Low Energy characteristic repeatedly in a short amount of time (as a possible use case, imagine a mouse). The characteristic with a 128bit UUID is…
Etan
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How do I get binary byte length in Erlang?

If I have the following binary: <<32,16,10,9,108,111,99,97,108,104,111,115,116,16,170,31>> How can I know what length it has?
0xAX
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com.mysql.jdbc.PacketTooBigException

I am storing images in MYSQL. I have table as CREATE TABLE myTable (id INT, myImage BLOB); When I am trying to insert 4.7MB file, I am getting exception as com.mysql.jdbc.PacketTooBigException: Packet for query is too large (4996552 > 1048576).…
Fahim Parkar
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Compression algorithm for JSON encoded packets?

What would be the best compression algorithm to use to compress packets before sending them over the wire? The packets are encoded using JSON. Would LZW be a good one for this or is there something better?
ryeguy
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Follow tcp stream - Where does field "Stream index" come from?

Wireshark has a that feature called "follow tcp stream", under the menu item "Analyze". When I use it, a screen capture filter is generated, something like: tcp.stream eq 1 Where does this index come from? I can't find any field in the packet that…
pcent
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