+++++++++ User space Process Communication, TCP Protocol basics, HTTP protocol Basics

Communication knowledge of the network process

Bare sockets, segments, shards, MTU

Process address, user space, kernel space

Inter-process communication, socket

TCP protocol

HTTP protocol

Hypertext definition, Hyper-text format

Web resources:

Dynamic

Static

Access to the portal, the resources being accessed

Cross-site references/hotlinking

Uri,url,run relationship, subset

URL format

Host address + process address (port)

Bare Sockets : TCP,UDP protocol Encapsulation message without calling the transport layer

Process Address : Port identification with TCP,UDP protocol, port (16bits)

IANA Internet Assign number Agent Internet address name Assignment Agency

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specific features : Process completion by user-space

Common functionality : When the process of user space is completed by the kernel, it is necessary to initiate syscall to kernel space when using common functions

Inter-process communication

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Socket: The kernel is provided by Syscall, the process in user space needs to communicate with the host across the network, it needs to be based on socket programming

Socket type

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Socket domain

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Socket programming

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TCP protocol

Based on SOCKET communication, Socket_stream

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MTU: Maximum Transmission unit

Segment: When the MTU size is greater than 1500bytes, the IP packets need to be segmented

Shard: When the path MTU minimum is less than 1500, fragmentation is required

HTTP protocol

Hyper Text Transfer Protocol Transfer Hypertext Protocol 80/tcp Socket_stream

Hypertext: Text developed by the HTML programming language (a link in a webpage jumps to another page, a link is called a hypertext link)

Hypertext format

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0.9 plain Text

1.0 support MIME, extension method, weak caching mechanism

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2.0 Mime,method, caching mechanism enhanced, spdy Advantage Integration (Spdy accelerate the acquisition of resources)

Working mode

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Requested content: Web content

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There are multiple resources in a page : Each page is a resource, each page has multiple hyperlinks, and each link corresponds to a resource

Access Portal : given address

Accessed Resource : The address referenced in the page

hotlinking/cross-site reference : A resource from a Web site from a resource on another server

URL: Identifies each resource or identifies the location of each resource

Subset of URIs: Url,urn

URL format

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Add

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Setfacl-m U:username:mode FILE ...

Setfacl-m G:groupname:mode FILE ...

Setfacl-x U:username:mode FILE ...

Setfacl-x G:groupname:mode FILE ...

This article is from the "Reading" blog, make sure to keep this source http://sonlich.blog.51cto.com/12825953/1967781

+++++++++ User space Process Communication, TCP Protocol basics, HTTP protocol Basics