osi protocol stack

pointers * that refer to this pbuf. this can be pointers from an application, * the stack itself, or pbuf-> next pointers from a chain. count the number of pointers pointing to this pbuf. these pointers may be applied. Program The pointer of the protocol stack, or the pbuf-> next pointer in the data link. The pbuf */u16_t ref can be released only when the ref is

TCP has a timeout retransmission mechanism, which should be familiar to everyone. TCP is a reliable transmission protocol, so this mechanism is essential. So today we are going to discuss how the protocol stack processes the data when the sending queue has data and the network connection is disconnected unexpectedly, how are resources recycled? Here are some te

Function call relationships in the tcp protocol stack during tcp three-way handshake in the Linux kernel-Linux general technology-Linux programming and kernel information. For more information, see the following. Recently, I need to modify a set of tcp protocol stacks. I simply looked at the function calling process of the kernel tcp

entry to greatly reduces the CPU waiting Tim E,and user policies is instead stored as a hash table not a list. The connection table and userpolicy is Per-numa, this would avoid CPU through QPI waste much time and increase delay.Second, FAST NAT does not record the TCP status,But the record a tuple with relevant connection formation for NAT forward.This can reduce the much check for forwarding packet.Entry in the connection table can is set to expire onAn absolute expiration time or relative exp

Synereo has released two new products to expand its R-chain blockchain infrastructure. Special-k and Rholang are likely to compete fiercely with Ethereum. The potential of blockchain technology is almost limitless. Synereo, an Israeli company based in Tel Aviv, recently announced a major advance in the de-centralized storage protocol. The company created the first extensible, Turing-complete blockchain infrastructure, R-chain. In the weeks followi

OPS-> Create function is called. We have previously seen that for af_inet, this callback function is the inet_create function of net/IPv4/af_inet.c, this function is used to create a socket. Because the function is relatively long, the analysis is skipped here. The first analysis is just a rough process. Because of socket creation and communication, this code is protocol-related, so the code is extracted from the original TCP. C.The following is the

At startup, it takes some time to fully load and initialize the Bluetooth protocol stack. You can use bth_namedevent_stack_inited to check the protocol stack initialization, which is defined in % _ winceroot %/public/common/SDK/INC/bt_api.h. To open this naming event, you must use OpeneventFunction. // Determine wh

netty--Private Protocol stack Development Case summary:In the study Li Lin Teacher's Netty authoritative guide, feel that the 12th chapter "Private protocol stack development" in the case code is more representative, said is also good, but the code of the individual think some simple error, the individual after a simpl

The morning turned on inexplicably can't internet, network cable not, WiFi also not.With IE diagnostics display "Windows cannot automatically bind the IP protocol stack to the network adapter", Baidu a bit, fortunately solved:Open "open Network and Sharing Center-change adapter Settings", right-click "Local Area Connection" or "Wireless network Connection", click "Properties", in addition to "Microsoft Netw

Because of the functional requirements of the project, you need to port the bluez Bluetooth protocol stack to the S3C2410 development platform. Many problems occur during the transplantation process, such as the version mismatch of the dependent library, the cross-compiler version is too high or too low. In order to reduce the migration detours, We will summarize the combined version and compilation process

Is it necessary to redesign the HOOK Point Location of Netfilter? Undoubtedly, this is meaningless because you cannot prove that the new solution is better. You may just look at the solution of another platform, which is different from the Netfilter solution. In fact, I am such a person.The Cisco ACL can be compiled on the port. In fact, the network port role of the Cisco device can be defined. The concept of Linux is completely different from this, linux Kernel considers role-defining as the re

0 With embeddedSystemAndNetworkMore and more embeddedDeviceTo achieve Internet network and support the access of embedded devices to the network, it has become an important part of the embedded field.ResearchDirection. A large number of Embedded SystemsApplicationLow SpeedProcessor, Restricted by memory and speed,Complete TCP/IPProtocolLWIP is widely used as a mature embedded TCP/IP protocol stack..

In Linux based on bacnet-stack-0.8.0 Engineering, bacnet protocol packet is sent through wireless network card. the Linux environment is Ubuntu12.04 + USB wireless network card (09 annual output of mercury MW54U, relatively old) 2. after compiling the target file in the normal way, 3. run the program in the/bin directory: run it... in Linux based on bacnet-stack-

A database on the server appears ' Ora-12516:tns: The listener cannot find an available process that meets the protocol stack requirements ' error, to resolve the problem first look at the number of existing processes in the database, whether the parameter processes has reached the size.Sign in with the system accountA.select COUNT (*) from v$process; Gets the current number of processes in the database.B.s

, inet_dump_fib ); Register_pernet_subsys ( fib_net_ops); register the protocol stack subsystem, that is, the routing system. Key Point: maid Register_netdevice_notifier ( fib_netdev_notifier); notification link RegistrationRegister_inetaddr_notifier ( fib_inetaddr_notifier );Fib_hash_init () Fib_hash_init () This function appears in both the fib_hash.c fib_trie.c files. The system can configure two rou

32bit field. If the system does not have accurate UTC or does not update at least 15 times per second, it is not treated as standard time. Non-Standard Time must set the high position of the timestamp field. There are three TIMESTAMP options. NET/3 is accessed through the ip_timestamp structure shown in. The three TIMESTAMP options specified by ip_flg are as follows: The initial host must construct a timestamp option with a sufficient data area to store possible timestamps and addresses, when t

Original: http://blog.chunshengster.me/2013/12/mobile_tcp_stack_optimizing.html http://blog.chunshengster.me/2013/12/optimizing_your_linux_stack_for_maximum_mobile_web_performance.html [Translate, See the original: Http://blog.cloudflare.com/optimizing-the-linux-stack-for-mobile-web-per Https://docs.google.com/presentation/d/1f2J_HrzMNvVHhsB3f7DKJFPl2N0 Q_Q r2zeecwqu6ov8/present#slide=id.p19 Google's great God on High performance browser network

file and Lib library to a directory such as/usr/inclue;/usr/lib, and directly write # include At this time, we will re-compile our project, smoothly compile and generate osipparser2.dll. At this time, many documents on the Internet may directly say that this step will also generate the libs directory, which contains the osipparser2.lib file, but we didn't generate it here :)The simplest method is to directly create a project without further research. Create a Win32 static Link Library Project a

GPON protocol StackFirst, the Gpon protocol stack is divided into two parts1. c/m plane----A, embedded OAM B, Ploam C, OMCI2, U (user) plane----A, high-level B, GTC layer C, physical layerSecond, c/m planeThe management control plane is divided into 3 parts:1, ploam Physical layer OAM, the main management delay requires low management, ONU registration, ranging,

How can I do this without Ethernet for Iot!Based on enc28j60, our team independently implemented the Ethernet protocol stack tinyip. Currently, ARP, ICMP, TCP, UDP, and DHCP are supported, and only one DNS is complete.Tinyip has a built-in data buffer. After receiving the data, enc28j60 puts it into the buffer zone, tinyip then splits and restructured the data based on the Ethernet/arp/IP/ICMP/TCP/UDP/DHCP