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easy to detect and fix: 5 days or less (this is based on data from large-scale real-time systems that have passed heavyweight SDLC, massive review and testing ). But there are also disgusting bugs. Even if you can easily reach it, you still have to "Work hard" to fix it. Discovery/Repair Repair time Repair Time> 5 days Able to reproduce Problems 72.5% 18.4% Difficult to reproduce or simply unable to reproduce

project management by Johanna Rothman The myths of innovation by Scott berkun Release it: Design and deploy production-ready software. By Michael T. Nygard Continuous integration: Improving Software Quality and cing risk by Paul Duvall, Steve Matyas, Andrew GLOVER Head first SQL your brain on SQL: a learner's Guide. By Lynn beighley The rails way. By Obie Fernandez Xunit test patterns: refactoring test code by Gerard meszaros 2009 Adrenaline junkies and template zo

5.58M, which is used for data transmission over FTP. Binary algorithms and HASH Sorting are applied during the transmission process. From the experiment results, we can see that in the same network environment, HDLC is a little faster than PPP under normal circumstances. After compression, both Protocols are significantly faster than before compression. Why? Let's start with their structure. HDLC (High-level Data Link Control), Advanced Data Link Control. The predecessor was the bit-oriented pr

related protocols, transmit the data packets to the receiving location through the IP network, and then concatenate the voice data packets. After decoding and decompression, the original voice signal is restored to achieve the purpose of transmitting voice over an IP network. The IP telephone system converts analog signals of ordinary phones into IP data packets sent by computers over the Internet, and also converts received IP data packets into analog electrical signals of sound. ◆ DLSw Techno

The foundation of the network is the establishment and application of many computer network protocols. So how can we understand this concept? The following describes the overview of computer network communication protocols. Network Communication Protocol (Network Communication Protocol )) it is a set of definitions of the Information Format for communication between computers and the transfer content that can be received or accepted by both parties. to implement the OSI Layer-7 reference model f

resulting polynomial should meet the following criteria:A, the highest and lowest bits of the generated polynomial must be 1.b, when the transmitted information (CRC code) any one error, is generated polynomial modulo 2 after the addition, should make the remainder is not 0.C, different bits when errors, should make the remainder different.D, the remainder to continue to do modulo 2 in addition, should make the remainder cycle.The main generation polynomial g (x) has the following types:

development team includes: User, project leader, analyst, junior Programmer, data clerk, operator.Software engineering refers to the use of engineering concepts, principles, techniques and methods to develop, maintain, and test the time to prove that the right management technology and the current can getThe best technical methods combine to guide the development and maintenance of computer software in engineering disciplines.Software engineering emphasizes the use of life cycle methodologies,

"Berkeley socket", can be seen Berkeley for the development of the network of how much contribution.The OSI System Reference model and the TCP/IP system comparison: OSI seven-layer model TCP/IP four layer model Corresponding network protocol Application Layer (application) Application Layer Telnet,ftp,tftp,smtp,http,dns ... Presentation Layer (Presentation) Text: Ascii,ebcdic Graphics: tiff,jpeg,gif,pict sound: Midi,mpeg,quickti

OSI (open System Interconnection), open Systems Interconnect Reference Model. From bottom to top seven-tier model features and their representative protocols: Physical Layer (physical) : Specifies the mechanical, electrical, functional, and process characteristics that activate, maintain, and close communication endpoints. This layer provides a physical medium for the upper level protocol to transmit data. bit, bit. Typical protocol representatives: eia/tia-232, eia/tia-499, v.35, v.24, RJ45

corresponds to each layer in the TCP/IP protocol model:3. Encapsulation and decryption of data:4. OSI Network architecture layer protocols:(1) Application layer: TELNET, FTP, TFTP, SMTP, SNMP, HTTP, BOOTP, DHCP, DNS(2) Presentation layer:Text: Ascii,ebcdicGraphics: tiff,jpeg,gif,pictVoice: Midi,mpeg,quicktime(3) Session layer: NFS, SQL, RPC, X-windows, ASP (apptalk Session protocol), SCP(4) Transport layer: TCP, UDP, SPX(5) Network layer: IP, IPX, ICMP, RIP, OSPF (Open Shortest Path First)(6) D

understanding the English version of the ISO8583 specification is a bit difficult, online also has a peer for our translation of the Chinese version of the ISO8583 specification, So my goal is to reach the reading of this article can be known to ISO8583, but also know the reason why, so that the basic non-contact with it before the people can also achieve the mastery of ISO8583 message specification.Well, it's time for us to turn to the chase.At first, the financial system was only IBM's big co

The role of each layer of the OSI Reference ModelPhysical layer: Transmits the raw data bitstream on the physical media.Data Link layer: Divides data into data frames and transmits them in a data frame. There should be a reply, the wrong re-hair.Network layer: The data is divided into a certain length of grouping, will be grouped through the communication subnet, select a path from the source to upload to the message.Transport layer: An efficient, cost-effective, transparent, end-to-end data tra

. Its main functions include: Physical address addressing, data framing, flow control, data error checking, re-sending and so on. It is independent of the network layer and the physical layer, and works without worrying about whether the computer is running software or other operations. The Data Link layer protocol includes: SDLC, HDLC, PPP, STP, Frame Relay, and so on.the third layer of the OSI model: Many users of the network layer often confuse the

or less (this is based on large-scale real-time systems through the heavyweight SDLC, extensive review and testing of data). But there are also very nasty bugs, even if you can easily find it, still have to "painstaking" to repair. Discovery/Repair Repair time Can reproduce the problem 72.5% 18.4% Difficult to reproduce or impossible to reproduce 5.9% 3.2% So if you bet that you can fix bugs quickly, most of the time you're right. But when you lose

. 12. Think. Think about what's wrong and what's wrong? Why is your fix working? Where will this type of bug appear? In the book "The Pragmatic Programmer", Andy Hunt and Dave Thomas also pointed out that "if a bug takes a lot of your time, make sure you understand why." In addition, there is a need to think about how to draw lessons and not cropper on similar issues in the future. And, do we use the method, the tools used to improve the place? and the impact and severity of these bugs. Find a b

-beijing-00016 Responsibilities be responsible for the complete lifecycle of software development, including designing, prototyping, Impl Ementation, testing, maintenance and technical support produce technical specifications and determine operational feasibil ity Write Well designed, testable, efficient code Develop software verification plans and quality assurance procedures INT Egrate software components into a fully functional software system Document and maintain software functionality Tail

This is a creation in Article, where the information may have evolved or changed. Liveblog by Beyang Liu (@beyang) Update: slides for this talk has been posted here. Improving operations in GO programs Ian Schenck, software engineer, Infrastructure at Oscar Insurance (ian.schenck@gmail.com). "I am a SWE who ends to SRE." Ian tries to write operable code. In the other words, he assumes it's going to broke at some point and tries to make it easy as possible to diagnose what went w Rong. This was

How should we understand network communication protocols? Can we fully master the increasingly complex network structures? We need to rely on network communication protocols for learning and understanding. Network Communication Protocol (Network Communication Protocol )) it is a set of definitions of the Information Format for communication between computers and the transfer content that can be accepted by both parties. To implement the OSI Layer-7 reference model function, each layer has many c

1. unpack 1. preparation tools JAVA environment, signature tools, 7zip compression software Jave download: http://sdlc-esd.sun.com/ESD6/JSCDL/jdk/6u20-b02/JavaSetup6u20.exe? Authparam = mirror groupname = JSC filepath =/esd6/jscdl/JDK/6u20-b02/javasetup6u1_exefile=javasetup6u20.exe bhost = javadl.sun.com signature tools: http://code.google.com/p/opm-server-mirror/downloads/detail? Name‑auto-sign.zip can = 2 Q = 7-zip compression softw

organization and the tester are included. The best practices that benefit both organizations and groups are described in this article. As Gartner said, by 2017, more than half of consumer goods manufacturers will reap 75% of consumer innovation and R D capabilities from the Medium-reporting solution. According to a forte study, 47% of QA experts show that they know what group testing is and how it works, over 1/3 of them believe that the current situation of APP testing will change when using