Hello, everyone!
Today, I want to start to explain a new topic – ODN engineering and maintenance. This is the first article, and now I will introduce the basic concepts. Let’s get started.
ODN is abbreviated from Optical Distribution Network. It is one of the three main segments of any PON system. For the normal functioning of the PON system, quality implementation and maintenance of ODN are required.
Figure 1. PON system
The task of ODN is to connect OLT (located in Headend or CO (Central Office)) and ONUs (located in users, in buildings, or outdoor cabinets).
There are different scenarios of FTTx (Fiber To The x) and POL (Passive Optical Local Area Network), it depends on the location of ONU. The most important FTTx solutions and POL are:
FTTH (Fiber To The Home). It is the most popular and best solution. The ONT device is located in the user's house. It is intended for one user only;
FTTB (Fiber To The Building). It is used in situations when the realization of FTTH is impossible. ONU is located in the building and is intended for a larger number of users in the building. Existing telephone or UTP cables are used for users;
FTTC (Fiber To The Curb). A similar situation as with the previous solution. ONU is located in the outdoor cabinet and is intended for a large number of users. Existing telephone cables are used for users. And,
POL (Passive Optical Local Area Network). This is a new solution for LAN. There are generally three OLAN solutions: FTTO (Fiber To The Office), FTTD (Fiber To The Desk), and POL. POL is the most popular solution. There are many advantages to the POL solution over the traditional LAN solution. POL is a complete PON system: OLT, ODN, and ONU.
This is the end of this article. I will explain this topic in the next article >> ODN Engineering and Maintenance (2).
Thank you!
Reference:
HCIA-Access, ver. 2.5, Huawei Access Certification Training
