FTTH Telecom Consultancy

15/07/2023

FTTH using CGNAT
As Public IP need to assign in order to give Internet Access to any Device/CPE.

Issue :As FTTH customers are huge numbers ,Its difficult for an ISP to give public IP for each customer.In this Case CGNAT (Carrier-grade NAT) technology is used and simply translate.

Internet Assigned Numbers Authority (IANA) allocated address block for CGNAT is 100.64.0.0/10, i.e. IP addresses from 100.64.0.0 to 100.127.255.255

As ONT is getting WAN internet IP address from BNG device via PPOE protocol. While OLT & PE devices just serving the purpose for MPLS & GPON infrastructure.

Above FTTH scenario ONT at home is getting IPv4 address assigned by BNG device 10.234.135.219 gateway:10.234.255.254 (Assigned to WAN ip of ONT device at Home).It forwarded to CGNAT Device .

CGNAT Devices having Pool of Private (100.64.0.0/10/10) and Public IPs (Any) and Perform NATing(Translate Private into Public) and Forward toward ISP for internet reachability,

Below example command from CGNAT Device for translation (A10 vendor).

19/05/2023

Open Access is a model that allows for the deployment and operation of fibre-to-the-home (FTTH) networks in a cost-efficient way. Building one infrastructure that is accessible to all service providers is in fact very cost-efficient, and has a significant impact on national coverage and market value.
Attached Diagram showing Basic scenario of Open Access of FTTH Home user.
User is looking for internet services for Operator B and outside his house Available fiber (ODB Box) of Another Operator A.In Such scenario both Operators will do configuration in their GPON/MPLS Network as per Open Access Network Agreement.
Below Steps will be followed in order to provide internet Service:-
1. Operator A provide fiber from OLT to ONT.
2. Operator A will configure Its GPON/OLT with bridge vlan.
3. A will Configure Its MPLS Network and Pass this vlan till Its Last HOP device and forward Operator B .
4. Operator B will configure its MPLS Network and Pass this vlan till BRAS Device.
5. Operator B BRAS will communicate to Customer ONT via PPOE .
6. Operator B BRAS uplink will communicate with IGW Network for Internet .

07/01/2023

GPON TRAFFIC FLOW IN NETWORK
IP Network (Ethernet Frame)==OLT (GEM Frame)==ONT(Ethernet Frame)

OLT Broadcast All Data (GEM1,GEM2…) to ONTs,but in ONT it will filter using Port ID in GEM Frame , Once ONT Receive GEM Frame will process only data which belongs to it. OLT Assigning different time slot to each ONT.and ONT can only send back data on that specific time slot assigned by OLT.

Data Transmission ;Downstream:
Downstream :From OLT to ONT (User)

Max 2.5 Gbit/s Wave length Downstream: 1480 nm-1450 nm , 1490 ;data packet transmitted in an broadcast manner (AES encryption used to prevent eavesdropping)

Data Transmission ;Upstream:
Upstream :From ONT (User) to OLT

Max 1.25 Gbit/s ,Wave length Upstream: 1290 nm – 1330 nm (narrowed) , 1310 nm;

ONTs are located at different distance ,(same wavelength + Same fiber ) so data packet transmitted in a TDMA manner .

1.Distance OLT-ONT measured.

2.Timeslot allocated according to distance.

3.ONT send upstream according to granted timeslot.

04/09/2022

GPON FTTH

27/08/2022

TL1 Integration Scenario

27/08/2022

TCONT Diagram

26/08/2022

https://chenabtel.com/tl1-protocol/
TL1 Protocol for configuring FTTx Services

TL1 Protocol by pk-admin Gpon Transaction Language 1 (TL1) It is a TCP connection-based cross-vendor, cross-technology man-machine language, and is widely used to manage/Provisioning broadband access infrastructure . Using TL1 we are passing input and output messages between Operations Support Sys...

20/08/2022

https://chenabtel.com/what-is-bras/
What is BRAS in Telecom?

17/08/2022

https://chenabtel.com/gpon-integration-scenarios/

GPON Integration Scenarios by pk-admin Gpon FTTx Internet Service Scenario To achieve internet services at user home/office/building via FTTx ,multiple integrations implemented in Operator network from GPON toward MPLS Network & IGW and to improve resource also other elements CGN,DPI ,RADIUS .Briefl...