ports and protocols

What is difference between nsnotification and protocol? (The difference between the notice and the agreement?) ）I think we all know how to use this thing, but the deeper thinking may be less, it is well known that the agent is one-on, but the notification can be many-to-many. But why is this like this, have you ever thought about the problem?Today, I saw a few video tutorials on the internet, KVO, KVC, predicates, notifications, is the development of advanced points of things. Notifications and

The current operating system basically implements the TCP/IP protocol. The TCP/IP protocol stack is divided into five layers: Application Layer: A group of common applications provided to users, such as telnet, FTP, SMTP, SNTP, DNS, and HTTP, which have a port to identify. Transport Layer: The main protocols are TCP and UDP, which provide application communication. Network Layer: The main protocol is the IP protocol, which defines the IP address forma

When Adobe, Microsoft, Sun and a series of giants began to show the "open source" of favor, "open source" era is coming!Originally from: sinoprise.com/read.php?tid-662-page-e-fpage-1.html (unfortunately this link has not been opened), I basically did not change, just some typesetting and collation.Reference: http://www.fsf.org/licensing/licenses/There are many open source agreements that exist today, and there are currently 58 (http://www.opensource.org/licenses/alphabetical) Open Source Initiat

VoIP intercom systems, the qutecom software interface is as follows: Ii. Official qutecom website Qutecom open source Official Website: http://www.qutecom.org/ As follows: Iii. Introduction to sip and RTP protocols 3.1 sip Overview SIP is an application control (signaling) protocol proposed by IETF [1]. As the name implies, it is used to initiate a session. It can be used to create, modify, and end multimedia session processes a

WCF provides a rich set of pre-binding protocols. These pre-binding protocols have developed the corresponding security mode at the beginning. This document lists the Security modes and verification methods of common protocols. 1. basichttpbinding Initial security mode: None Initial Message Security Client credential type: Windows Initial Transport seci

Common protocols: GPL, BSD, MIT, Mozilla, Apache, and lgpl For details about the differences between protocols, refer to [reprint] how to select an open-source license? A detailed explanation of each protocol is as follows: 1. GPL: detailed introduction to the GPL Protocol 2. BSD: Introduce BSD open source protocol in detail 3. MIT: detailed introduction to the MIT Protocol 4. Mozilla: MPL (Mozilla Public L

The dynamic routing protocol is also an important part of the routing protocol. Many people may not know the detailed knowledge of RIP, OSPF, and VPN in the dynamic routing protocol, after reading this article, you must have gained a lot. I hope this article will teach you more things. We have already briefly introduced three types of Dynamic Routing Protocol algorithms: Distance Vector Algorithm, link state algorithm, and balanced hybrid algorithm. Let's take a look at the types of these algori

Currently, the vro protocol is widely used. Many people may not know the RIP, HELLO, and egp in the vro protocol. It does not matter. After reading this article, you will certainly have a lot of GAINS, I hope this article will teach you more things. Technically, the IGP protocol is the same as RIP and HELLO protocol. Vro uses this Protocol to obtain information about other vro protocols in the autonomous system so as to update its routing table. Unlik

We know the excellent performance of IPV6 network protocol, and the most widely known is that it solves the problem of address resource depletion. However, it has other advantages in many ways. The following describes the security of IPV6 network protocols. I believe this is also a matter of concern to everyone. With the development of China's routing industry, the router technology is constantly updated and upgraded. Compared with IPv4, IPV6 has many

With the development of China's routing industry, it also promotes the improvement of router protocols. The TCP/IP-based Internet has gradually developed into a super-large computer network with the largest number of users and the largest resources in the world. Therefore, TCP/IP has become a de facto industrial standard. IP networks are gradually becoming the mainstream of modern and future computer networks. An IP network is composed of IP subnets c

We have reviewed the routing protocol above. For the routing protocol, we can classify it into two categories: category and category-free. First, let's take a look at the concept of classless routing. Classful routing) Overview The routing selection protocol that does not send subnet mask information with each network address is called the classification selection protocol r12001 and IGRP.) When a classification routing selection protocol is used, all subnetworks must use the same subnet mask. A

1:Compile the following three modulesOption 2:Compile the following four modules4. Compile the kernel, install the module, install the kernel [root @ zhangc linux-2.6.25.19] # make [root @ zhangc linux-2.6.25.19] # make modules_install [root @ zhangc linux-2.6.25.19] # make install5. Uninstall older versions of iptables [root @ zhangc ~] # Rpm-e iptables-nodeps6. disassemble and merge iptables + layer7 Patch [root @ zhangc ~] # Tar jxvf iptables-1.4.2.tar.bz2-C/usr/src/[root @ zhangc ~] # Cd/us

implemented on the terminal system, instead of on the network router. The network router only acts on the network layer field of 3-PDU, not the transport layer field. Figure 1 layer-7 network protocol model transport layer provides logical rather than physical communication between two applications At the sender, the transport layer converts messages sent by applications into 4-PDU (transport layer protocol data units ). the process of constructing 4-PDU is to divide the application message

Among our commonly used devices, one is a router and the other is a switch. These two types of devices are all important for network management. So today we will give a brief introduction to the relevant content of the IP switch. These include GSMP and IFMP. To master the GSMP and IFMP protocols, we need to understand the concept of IP exchange. Next, let's take a look at the basic concepts of IP exchange. Basic concepts of IP address exchange IP exch

Basic overviewThe primary function of the transport layer is to provide end-to-end communication to applications on two hosts, identifying the correspondence between the corresponding programs on the two hosts via the port number. The most important two protocols in the transport layer are TCP and UDP, which can be used to identify the protocol type that transmits the data based on the Protocol field of the IP header. TCP is a connection-oriented, rel

Http://conanwhf.gitcafe.io/2016/01/30/rpi-protocol/?hmsr=toutiao.ioutm_medium=toutiao.ioutm_source= Toutiao.io implementation of several simple protocols on Raspberry Pi posted on 2016-01-30 | Categories in Raspberrypi | No Comments The procrastination of his own is really disciplining, this is a delay to abandon the article. Fast New Year, how can not be dragged into the years after the spirit, clear the list. To create a small home environment moni

Switching Mode for resources, and the peer-to-peer bidirectional 64 kbit/s fixed bandwidth channel provided for both parties of the communication is not suitable for data services with large burst data volumes and large differences in upstream and downstream data traffic ｡ The wide area network (WAN) protocol can be divided into DDN, X.25, frame relay, and IP network, because the IP network has simple protocols, low terminal device prices, and the de

For a vro, an important network product, there is always endless learning about it. So what is the principle of this Router Based on? This is what we usually call the class routing protocol. Next we will summarize all the router protocols. Before that, let's take a look at the prerequisites for using this protocol. 1. When will I use the multi-Router Protocol? When two different routing protocols need to ex

Before we start, let's start by thinking about several questions. What is a route? What are OSPF and BGP? What are their purposes? What are their application scenarios? What are the advantages of the two routing protocols in OpenBSD compared with hardware routers such as Cisco/Huawei? How to Use OpenBSD to reduce network costs? 1. What is a route? Simply put, a route is like a sign at a crossroads, and an IP packet is like a car on the road. Wh

Introduction and classification of dynamic routing protocols different routing protocols use different measurements, and sometimes multiple measurement hops bandwidth Load Measurement reflects the traffic usage of links along the way; unlike the number of hops and bandwidth, the load on the path changes, so the measurement also changes. If the measurement changes too frequently, the routing swing (the Optim