Microsoft Project (ou MS Project ou MSP) est un logiciel de gestion de projets édité par Microsoft. Il permet aux chefs de projet et aux planificateurs de planifier. Die PC-FAQ enthält Antworten zu vielen Fragen rund um den PC, sowie Erklärungen der häufigsten Computerbegriffe und ein Wörterbuch. A Comprehensive Guide to Project Management Software Solutions. The project management software industry is currently dominated by a number of key software big. Description : Logiciel complet et très performant. Une alternative crédible à Microsoft. Le logiciel est développé par Sciforma. Générations de produits : PSN. Installing and Testing Copper Cabling in LANs . Each individual implementation of Ethernet specifies parameters for the intended medium, but usually references other cable related standards as part of that description. This chapter and Chapter 3, . All the older standards (prior to TIA/EIA- 5. A TSB6. 7, which was approved in October 1. Information about links in general, and information specific to twisted- pair LAN cables, is provided in the text that follows. Note that the term link is used to describe installed assemblies of cabling components; that is, connectors and cable. As the networking industry matures, it is interesting to note which technologies emerge as dominant and to track which specifications and technologies are omitted. For example, one of the earlier documents that defined cable requirements for networking applications was the Underwriters Laboratories document . This document reviewed IBM's Cabling System Technical Interface Specification (GA2. Type 1 and Type 3 cable. It also provided detailed performance requirements for the following cable types that have evolved into the current Category 3 and Category 5 cables referenced by TIA/EIA- 5. A. Table 2- 1. Early 1. Underwriters Laboratories LAN cable grades (historical reference only)Cable Grade. Operating Frequency. Use. Level I(No performance criteria found)Telephone and power- limited circuits. Level IIUp to 1. MHz. Similar to IBM Type 3. Level III1. 50k. Hz to 1. MHz. Approximately the same as Category 3. Level IV7. 72k. Hz to 2. MHz. Slightly better than Category 3, never widely adopted. Level V7. 72k. Hz to 1. MHz. Approximately the same as Category 5. Category 3 and Category 5e are the only ones described by the 2. TIA/EIA- 5. 68- B (see Table 2- 2). Category 5 is explicitly described as a legacy cable specification. Depending on how cheap Category 5e becomes, and on how tenacious the low- speed protocols are (such as 1. BASE- T), Category 3 is likely to disappear entirely, or may be used for technologies such as telephone and x. DSL. TIA/EIA- 5. 68- B includes a statement to the effect that although 1. STP- A) cable is still mentioned, it is not recommended and is very likely to be removed from the next full release of the TIA standards entirely. An example of how cabling standards evolve is provided in Table 2- 3. Table 2- 2. ISO/IEC 1. TIA/EIA- 5. 68 cable grades for balanced cable as of March 2. ISO/IEC Cable Grade. Operating Frequency. TIA/EIA Cable Grade. Operating Frequency. Class AUp to 1. 00. KHz——Class BUp to 1. MHz——Class CUp to 1. MHz. Category 3. Up to 1. MHz. Class DUp to 1. MHz. Category 5e. Up to 1. 00. MHz. Class EUp to 2. 50. MHz. Category 6. Up to 2. MHz. Class EAUp to 5. MHz is proposed. Category 6. AUp to 5. 00. MHz. Class FUp to 6. 00. MHz——Class FAUp to 1. MHz is proposed——Table 2- 3. Evolution of high- speed twisted- pair link specifications as extracted from the obsolete TIA/EIA- 5. A standard, the current TIA/EIA- 5. B. 2 and TIA/EIA- 5. C. 2 standards. TIA/EIA- 5. ATIA/EIA- 5. 68- BTIA/EIA- 5. CTSB6. 7TSB9. 5Addendum 5. TIA/EIA- 5. 68- B. TIA/EIA- 5. 68- C. Unlike the earlier version, TIA/EIA- 5. B was published in three sections. TIA/EIA- 5. 68- B was updated regularly following release. Part 1 (TIA/EIA- 5. B. 1, General Requirements) covers general requirements for planning and installing a structured cabling system. That is, everything from the configuration and requirements for the rooms that house the cable and equipment (see also ANSI/EIA/TIA- 5. A), up through the electrical safety requirements (see also ANSI/TIA/EIA- 6. ANSI/TIA/EIA- 7. 58) and the actual network cable selection, installation, and testing requirements for both twisted- pair copper and fiber optic cables. Part 2 (TIA/EIA- 5. B. 2, Balanced Twisted- Pair Cabling Components) is mostly concerned with the connecting hardware and cable components used in 1. Several appendixes define the testing requirements for those components and for testing cable assemblies (patch cables and horizontal cabling). Updates have been released regularly, such as TIA/EIA- 5. B. 2- 1, which was approved in June 2. Addendum 1 to the basic standard, and defines the performance specifications and test requirements for Category 6 cable and components. Addendum 1. 0 defines Augmented Category 6 (Cat 6. A) link performance requirements (approved February 2. The TIA published Technical System Bulletin 1. TSB- 1. 55) to define the cabling performance and field test requirements for the 1. GBASE- T application as defined in IEEE standard 8. Note that Category 6. A demands a higher level of performance than TSB- 1. MHz and especially for . Required test parameters for 1. GBASE- T support for TIA and ISO cabling standards. TIA/EIA- 5. 68- B and TSB- 1. ISO/IEC 1. 18. 01 and TR - 2. Wiremap. MMDC Loop Resistance. IMLength. MIPropagation delay. MMDelay skew. MMInsertion loss. MMReturn loss measured from both ends. M (1)M (1)Near- end crosstalk (NEXT) loss pair- to- pair measured from both ends. MM (2)Power sum near- end crosstalk loss (TIA) PSNEXT (ISO) PS NEXT calculated for both ends. MCMC (2)Attenuation to Crosstalk loss Ratio Near- end (TIA) ACRN, (ISO) ACR- NNRMCPower Sum Attenuation to Crosstalk Loss Ratio Near- end (TIA) PS ACRN (ISO) PSACR- NNRMCAttenuation to Crosstalk Loss Ratio Far- End (TIA) ACRF, (ISO) ACR- F (formerly ELFEXT) pair- to- pair. MMCPower Sum Attenuation to Crosstalk Loss Ratio Far- End (TIA) PSACRF (ISO) PS ACR- F (formerly PSELFEXT)MCMCAlien Near- end Crosstalk (ANEXT) Loss. MMPower- Sum Alien Near- End Crosstalk Loss (TIA) PSANEXT (ISO) PS ANEXTMCMCAFEXT loss. M- Power Sum Attenuation to Alien Crosstalk Ratio Far- End (TIA) PSAACRF (ISO) PS AACR- FMMAverage PSANEXT Loss. MNRAverage PSAACRFMNRI = Informational, M = Mandatory, MC = Mandatory (Calculated), NR = Not required by this standard. M (1) = If measured insertion loss value at the same frequency is less than 3d. B, the value is not used for Pass/Fail criteria. M (2) = If measured insertion loss value at the same frequency is less than 4d. B, the value is not used for Pass/Fail criteria. Note: Informational parameters are measured but not used for Pass/Fail criteria. The TIA/EIA- 5. 68- C standard update should be completely approved and published by Q3 2. As with TIA/EIA- 5. B, the document structure was reorganized. This text utilizes primarily TIA/EIA- 5. B references and final test requirements because full approval for TIA/EIA- 5. C had not occurred before the book went to press, and the requirements could still change. Part 0 (TIA/EIA- 5. C. 0) covers generic requirements for planning and installing a structured cabling system. Included are general requirements for architecture, length, grounding, bend radius, pulling tension, pinout, and polarity. Also included are general testing requirements. Part 1 (TIA/EIA- 5. C. 1) covers requirements for cable systems in a commercial building, or between commercial buildings in a campus environment. Provides the configuration and requirements for the rooms that house the cable and equipment (see also ANSI/EIA/TIA- 5. A), up through the electrical safety requirements (see also ANSI/TIA/EIA- 6. ANSI/TIA/EIA- 7. 58) and the actual network cable selection and installation requirements for both twisted- pair copper and fiber optic cables. Part 2 (TIA/EIA- 5. C. 2) covers the connecting hardware and cable components used in balanced twisted- pair cable networking applications. Provides the requirements and test specifications for components used to create an installed link, as well as the testing requirements for installed links. Part 3 (TIA/EIA- 5. C. 3) covers optical fiber topics.
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