Cabling recommendation TIA-942-B (2017)
- Category 6, 6A, or 8（Category 6A or higher is recommended）
- OM3, OM4, or OM5（OM4 or OM5 is recommended）
- Add MPO-16, MPO-24 and MPO-32 as options for termination of more than 2 fibres in addition to the MPO-12 connector
- Add 75-ohm coaxial cables and connectors in ANSI/TIA-568.4-D
Testing and verifying structured cabling
- Get 3rd party compliance proof such as ULZ ETS before confirmation of using a brand and new technologies, e.g. Cat 6A, Cat8, OM4 and OM5
- 100% testing and 3rd party testing to verify the installation
- Copper cable parameters to test
- NEXT / PS-NEXT / ELFEXT/ PS-ELFEXT
- Return loss / propagation delay / delay skew
- ANEXT (Cat6A only, seldom test on-site)
- Fibre testing
- Return loss / insertion loss / link testing
- Laser bandwidth DMD/ EMB not verifiable on site
Storage Area Networks (SAN)
- Allows for fast, flexible and redundant network-wide data storage
- SAN requires high-quality optic networks
- FC-AL (Fiber Channel Arbitrated Loop)
- Hub connects servers to storage
- Switch fabric
- High speed, low latency switches, preferred for enterprise-class networks
- Most SANs use OM3/4 multimode fiber
- Switch fabric needs lots of network points
- Plan capacity - use structured cabling
- Avoid point to point cabling clogging up the underfloor as it may result in poor cooling and a high risk of failure
Network redundancy
- Network diversity
- Network redundancy
- Redundancy on the backbone
- Redundancy in the data centre
- Redundant network equipment in sub-racks
- Redundant cable paths
- Separate office building management networks
- Ensure separate physical routes
如今，網絡的冗余是較易實現的，但要留意要做到物理上的冗余還是邏輯上的冗余。在某些數據中心，物理上的單點故障仍然存在，另外，即使在完全物理冗余的環境中，網絡也需要配置適當後備路由協議方案、後備虛擬IP地址等。
Building to building connectivity (1) - Telco 電訊公司
- Determine capacity needed
- Evaluate local telco capability
- Connectivity (speed/bandwidth)
- Uptime guarantees
- Service
- Pricing
- Budget appropriately
- Monthly subscription and/or usage fees
- Commonly an expensive option
- But if off-site is typically the only option for hardwired connections
第一個選擇是當地的電訊供應商（安全性存疑）。告知供應商網絡連接的地點、所需的連接速度、預期正常運行時間以及對服務水平潛在要求。通常情況下，電訊供應商會收取一次性的安裝費，之後按月收費，所以會長期交付一定的重覆的費用。
Building to building connectivity (2) - Hardwire 專屬線纜
- Copper/fibre cabling from building to building
- One-time only investment
- Time-consuming to install
- Commonly an expensive option
- What if you relocate
另一個選擇是在多個建築物之間自行鋪設專屬線纜。由於公共環境的限制，通常不允許在公共土地鋪設私有線纜，常見擁有較多土地的使用者，例如，大學校園等等。
Building to building connectivity (3) - Canopy 無線覆蓋
- Direct connection between points or as AP (access point)
- Range
- > 190 km as AP
- > 249 km as Point to Point
- Very good transmission speed
- Approx. 400 Mbps (PMP 450) with multi-point
- Approx. 500 Mbps (PTP820) point-to-point
- Security features (encryption)
- Reasonably prone to EMF / EMP
- One-time investment
無線覆蓋系統可以跨越長距離。能提供良好的傳輸，也容易出現安全問題。長距離傳輸，一次性投資，需要定期維護。
Building to building connectivity (4) - FSO 無線激光
- Free Space Optics (FSO)
- Direct connection between points
- Requires line of sight
- Advantages
- Many vendors
- High-bandwidth
- 1 Gbps - 30 Gb/s
- Good reach
- 1.5 km - 4.4 km
- Protocol independent
- Quality transmission
- Highly secure
- License-free worldwide
- One time investment
以激光為載體，兩個設備相互瞄準來傳輸網絡數據。存在的限制是這兩個設備間必須無遮擋的點對點連接。如果中間有建築物等障礙物，將無法傳輸。由於點對點連接，因此較為安全。如果一旦偵測到有人試圖攔截信號，連接將自動中斷。這類設備一般是一次性的投資，但在一些國家，需要每年支付一定的費用。
Network monitoring system required capabilities
- Flexible and versatile
- Multi-vendor support
- Supporting your network technologies
- ATM / Frame Relay / MPLS VPN & TE etc.
- Supports SNMP (Simple Network Management Protocol)
- V1 & V2
- SNMP V3 for secure networks
- Support for RMON
- Automated root cause analysis
- Notification capabilities
- Reporting capabilities
- Offline / Online
建議數據中心運營商購買一個較靈活多變的分析系統，並且支持較多廠商。分析系統一般都會支持SNMP V1和V2，但對於允許安全監控的V3標準並不總是支持。支持RMON技術，RMON可以詳細分析網絡連接，具備流量整形等功能。RMON能自動分析所有的硬件連接，查找問題的緣由。定期通知工作/管理人員，使其能夠持續地了解網絡的當前狀態。系統可以按照需要生成離線和實時報告。
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