30.7 Formal Definitions Using ASN.1 The SMI standard specifies that all MIB variables must be defined and referenced using ISO's Abstract Syntax Notation 1 (ASN.13). ASN.1 is a formal language that has two main features: a notation used in documents…

Applications: Internet Management (SNMP) 30.1 Introduction 30.2 The Level Of Management Protocols 30.3 Architectural Model 30.4 Protocol Framework 30.5 Examples of MIB Variables 30.6 The Structure Of Management Information 30.7 Formal Definitions Usi…

30.13 Summary Network management protocols allow a manager to monitor and control routers and hosts. A network management client program executing on the manager's workstation contacts one or more servers, called agents, running on the devices to be…

30.11 Example Encoded SNMP Message The encoded form of ASN.1 uses variable-length fields to represent items. In general, each field begins with a header that specifies the type of object and its length in bytes. For example, each SEQUENCE begins with…

30.10 SNMP Message Format Unlike most TCP/IP protocols, SNMP messages do not have fixed fields. Instead, they use the standard ASN.1 encoding. Thus, a message can be difficult for humans to decode and understand. After examining the SNMP message defi…

30.9 Simple Network Management Protocol Network management protocols specify communication between the network management client program a manager invokes and a network management server program executing on a host or router. In addition to defining…

30.8 Structure And Representation Of MIB Object Names We said that ASN.1 specifies how to represent both data items and names. However, understanding the names used for MIBvariables requires us to know about the underlying namespace. Names used for M…

30.12 New Features In SNMPv3 We said that version 3 of SNMP represents an evolution that follows and extends the basic framework of earlier versions. The primary changes arise in the areas of security and administration. The goals are twofold. First,…

30.6 The Structure Of Management Information In addition to the standards that specify MIB variables and their meanings, a separate standard specifies a set of rules used to define and identify MIB variables. The rules are known as the Structure of M…

30.5 Examples of MIB Variables Versions 1 and 2 of SNMP each collected variables together in a single large MIB, with the entire set documented in a single RFC. After publication of the second generation, MIB-II, the IETF took a different approach by…

30.4 Protocol Framework TCP/IP network management protocols2 divide the management problem into two parts and specify separate standards for each part. The first part concerns communication of information. A protocol specifies how client software run…

30.3 Architectural Model Despite the potential disadvantages, having TCP/IP management software operate at the application level has worked well in practice. The most significant advantage of placing network management protocols at a high level becom…

30.2 The Level Of Management Protocols Originally, many wide area networks included management protocols as part of their link level protocols. If a packet switch began misbehaving, the network manager could instruct a neighboring packet switch to se…

30.1 Introduction In addition to protocols that provide network level services and application programs that use those services, an internet needs software that allows managers to debug problems, control routing, and find computers that violate proto…

转自:http://www.rane.com/note161.html An SNMP Overview The Message Format The Actual Bytes Introduction Although some RS-232 connectors still cling desperately to audio hardware products around the world, for years Ethernet and the Internet Protocol (I…

这几天翻译一篇旧文 How browsers work ( 以现代浏览器chrome.火狐.safari 为对象来分析),这篇文章网上有其他的翻译版本,自己再翻译一遍主要是练习阅读英文文章,而且自己翻译记忆会更深刻. 原文链接:  http://taligarsiel.com/Projects/howbrowserswork1.htm#Introduction 简介 浏览器可能是使用最多的软件,我会分析现代浏览器是如何工作的,你将会了解从地址栏输入网址 "google.com" 到显示…

原文地址:https://dzone.com/articles/how-annotations-work-java Annotations have been a very important part of Java and it’s been there from the time of J2SE 5.0. All of us might have seen annotations like @Override and @Deprecated in our application code…

是任意形式的递归,是化解的一般式. 主题所谓的“递归调用化解为栈处理”,意思是,将递归函数调用化解为“一个由stack_push stack_pop stack_top等函数调用组成的循环式子”.这里的 stack_push, stack_pop, stack_top是指,程序员自己实现的一个ADT(Abstract Data Type)中的函数操作接口,这个ADT叫做栈.要知道,在C语言中,函数调用链本身就是栈处理的,处理C语言中函数调用链的是进程栈/线程栈,进程栈/线程栈是一个C语言程序运行…

Mahmoud and Ehab continue their adventures! As everybody in the evil land knows, Dr. Evil likes bipartite graphs, especially trees. A tree is a connected acyclic graph. A bipartite graph is a graph, whose vertices can be partitioned into 2 sets in su…

\subsection{Even and Odd Functions} For a function $f$ in the form $y=f(x)$, we describe its type of symmetry by calling the function \textbf{even}\index{even functions} or \textbf{odd}\index{odd functions}. An \textbf{even function} means $f(-x)=f(x…

Chapter 4. The class File Format Table of Contents 4.1. The ClassFile Structure 4.2. Names 4.2.1. Binary Class and Interface Names 4.2.2. Unqualified Names 4.2.3. Module and Package Names 4.3. Descriptors 4.3.1. Grammar Notation 4.3.2. Field Descript…

B. Mahmoud and Ehab and the bipartiteness time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Mahmoud and Ehab continue their adventures! As everybody in the evil land knows, Dr. Evil likes bi…

 Mahmoud and Ehab and the bipartiteness Mahmoud and Ehab continue their adventures! As everybody in the evil land knows, Dr. Evil likes bipartite graphs, especially trees. A tree is a connected acyclic graph. A bipartite graph is a graph, whose verti…

文章标题 One SQL to Rule Them All – an Efficient and Syntactically Idiomatic Approach to Management of Streams and Tables 用SQL统一所有:一种有效的.语法惯用的流和表管理方法 syntactically 句法上;语法上;句法;句法性地;句法特征 idiomatic [ˌɪdiəˈmætɪk] 惯用的;合乎语言习惯的;习语的 approach [əˈproʊtʃ] v.(在距离或时间…

KERBEROS PROTOCOL TUTORIAL   This tutorial was written by Fulvio Ricciardi and is reprinted here with his permission. Mr. Ricciardi works at the National Institute of Nuclear Physics in Lecce, Italy. He is also the author of the Linux project zeroshe…

管理信息库:MIB 我们要扩展mib首先必须清楚mib是如何定义的,用的什么语言,有哪些约定,遵循哪些规则等等.这些基本东西掌握过后,我们就可以很轻松的来写自己的mib文件了. 所谓管理信息库,或者MIB,就是所有代理进程包含的.并且能够被管理进程进行查询和设置的信息的集合,或者叫管理对象的集合,在RFC 1213 [McColghrie 和Rose 1991]中定义了MIB-II,即第二版的MIB库.MIB是采用SMI(RFC 1155)来定义的.SMI全称为Structure Managem…

SNMP SNMP 网络管理的历史 美国国防部设计了世界上头几个包交换网之一的ARPANET,在70年代,TCP/IP协议族正式被定为军方通信标准,随着此协议的广泛使用,网络管理成了一件大事.在80年代未和90年代初,网络迅速发展,许多子网数目的增多使监视网络活动成为一种必须. 在网络管理的初期,对网络的管理停留在使用ICMP和PING的基础上,但是随着网络内主机数据的不断增多,这种简单的工具已经不可能完成网络管理的工作了. SNMP历史 随着网络数目与网络内主机数目的日益增多,单纯依靠一些网络…

背景信息 http://datatracker.ietf.org/doc/rfc1213/ http://oid-info.com/get/1.3.6.1 http://oid-info.com/get/1.3.6.1.2.1 此下面包含220个子OID http://www.oidview.com/mibs/detail.html http://www.net-snmp.org/docs/man/snmpd.conf.html http://www.iana.org/assignments/e…

源地址:https://blog.csdn.net/carechere/article/details/51236184 SNMP协议的MIB文件的常见宏定义的描述: 对MIB文件中一些常见的宏定义的描述 1.DEFINITIONS ::= BEGIN SNMP始终使用ASN.1概念中的描述块(module)来组织ASN.1对象的,ASN.1的描述块是一些相关描述语句的集合,module的结构如下 <<module>> DEFINITIONS ::= BEGIN <<l…

1.1.    SNMP概览 SNMP的基本知识介绍简单网络管理协议(SNMP-Simple Network Management Protocol)是一个与网络设备交互的简单方法.该规范是由IETF在1990年五月发布的RFC 1157中定义的.SNMP通常被认为相当难懂,并且过于复杂,其可用的API似乎在本来非常简单的东西外面封装了大量的东西.现在关于SNMP的书籍又往往只是把它更加复杂化了,而没有解释清楚.SNMP对于任何程序设计人员来说是特别易于理解的.总体的简化能够很好地把这个系统简化…