The network layers use abstraction and encapsulation. The lower layers encapsulate the higher layers. The Application layer can have its own protocols, e.g. HTTP. HTTP communicates with HTTP on the target device, and it is a protocol that transfers the application data (HTML). The Transport layer (layer 4) encapsulates the application datagrams, and it communicates … Read more
No, message boundaries have nothing to do with destinations or ports. A “message boundary” is the separation between two messages being sent over a protocol. UDP preserves message boundaries. If you send “FOO” and then “BAR” over UDP, the other end will receive two datagrams, one containing “FOO” and the other containing “BAR”. If you … Read more
Message Oriented protocols send data in distinct chunks or groups. The receiver of data can determine where one message ends and another begins. Stream protocols send a continuous flow of data. Here is an example with mobile phones. Text messages would be a message oriented protocol as each text message is distinct from the other … Read more
InfiniBand adapters (“HCAs”) provide a couple of advanced features that can be used via the native “verbs” programming interface: Data transfers can be initiated directly from userspace to the hardware, bypassing the kernel and avoiding the overhead of a system call. The adapter can handle all of the network protocol of breaking a large message … Read more
You are exhausing the space of outbound ports by opening that many outbound sockets within the TIME_WAIT period of two minutes. The first question you should ask yourself is does this represent a realistic load test at all? Is a real client really going to do that? If not, you just need to revise your … Read more
Sorry, given your constraints (client-side Javascript only), there is no way to connect to a plain old SSH server. WebSockets is not plain TCP. It’s a framed protocol with a HTTP-like handshake between the client and server that includes origin policy. Flash can make plain TCP connections, but it also has origin policy enforcement. The … Read more
I know this is an old question, but i’ve also been in search for an answer. The previous answer does not make mention of the interval, so I searched through some code of some popular websocket frameworks. Not that this is official, but at least it gives a starting point: this repo makes use of … Read more
This problem has been debated on another question, see Adjusting HttpWebRequest Connection Timeout in C#. The discussion made my head spin, so I’ll offer my summary. Although, MSDN explains that the HttpWebRequest.Timeout Property applies to HttpWebRequest.GetResponse and HttpWebRequest.GetRequestStream calls, the description is a bit confusing. Jim Mischel is more helpful: Timeout “is the time for … Read more
You can’t assume that any stacked protocol is stateful or stateless just looking at the other protocols on the stack. Stateful protocols can be built on top of stateless protocols and stateless protocols can be built on top of stateful protocols. One of the points of a layered network model is that the kind of … Read more
The classic answer to this issue is to use 127.0.0.1 or the IP of the host or the host name instead of the “special name” localhost. From the documentation: […] connections on Unix to localhost are made using a Unix socket file by default And later: On Unix, MySQL programs treat the host name localhost … Read more