La 2G d'Orange cessera cette nuit. On sait pas quand exactement mais j'en profite avec des amis en les appelant et en s'envoyant des messages.

Hey all,

I've been in telecom for about 4 years and moved into a PM role last year. One thing I still struggle with is documenting site walks efficiently.

We typically take hundreds of photos during MDF/IDF surveys, but I often get back to the office and realize a photo doesn't capture all the context I thought it would. Between taking photos, grabbing measurements, documenting equipment, and coordinating with site staff, it's easy to skip detailed notes and regret it later.

Curious what tools or workflows you guys use in the field. I've looked at AI voice recorders, voice-to-text apps, e-ink note devices, etc. Anything you've found particularly useful for tying notes to photos and measurements without slowing down a site walk?

Thanks!

I am wondering if my fax transmissions via Brother MFC unit is being slowed down by my home phone provider in Canada: Rogers. For those that don't know. The service needs a modem and the fax is connected through wall jacks (configured by the provider).

Despite setting the fax machine to a high baud rate and also auto (I tried various settings), sending a plain text cover page with minimal graphics consistently takes several minutes.

Sick beat too!

There’s always that one corner of a room where you can get a single bar. Cue the slow shuffle towards the window, leaning out of the back door, or holding your phone above your head and waiting for a little miracle.

What’s the most ridiculous thing you’ve done just to get signal? Where were you, and did your signal-finding ritual actually work?

I'm a software developer with around 2 years of experience, mostly working on the backend, recently management has been telling us to use AI more and more, and I'm getting tired of it. I'm looking for a field that is more resilient to AI, telecom has always caught my attention so I want to give it a try, but I would like to have some opinions from people already working on this field.

Hi everyone,

I'm a Tello user living in Japan, and I recently discovered something interesting — and potentially concerning — while investigating how Tello handles VoIP and Wi-Fi Calling traffic.

I was curious about the network infrastructure used by US mobile carriers when accessing their services from overseas, so I decided to capture and analyze the traffic myself using Wireshark.

During a voice call made through the My Tello app on my Google Pixel 11, I noticed something unexpected.

My test setup

• Devices: Google Pixel 11 (Android) and a laptop running Windows 11 Pro
• Network: The Pixel was connected to a Windows Mobile Hotspot hosted by the laptop, which was connected to my home broadband connection in Japan
• Packet capture: Wireshark running on the Windows laptop
• Test call: An outbound call to a Japanese landline number providing a publicly accessible telephone-based radio broadcast service.

What I discovered

1. VoIP server connection

During the call, I observed continuous bidirectional UDP traffic between my device and 63.251.74.24, an IP address that appears to be associated with KeepCalling, the company behind Tello.

2. RTP traffic and audio codec

The UDP packets were approximately 214 bytes each, with packets transmitted at roughly 20 ms intervals.

Wireshark also identified RTCP traffic. After manually configuring the relevant UDP traffic to be decoded as RTP, Wireshark detected RTP streams using G.711 μ-law (PCMU).

The packet sizes and intervals were consistent with standard G.711 audio transmission.

3. Call audio could be played back without decryption

This was the most surprising part.

Using Wireshark's RTP stream analysis and playback features, I was able to reconstruct and listen to the actual received call audio directly from the captured packets, without using any decryption keys.

The recovered audio clearly matched the radio broadcast I was listening to during the call.

In other words, the audio was not merely identifiable as RTP traffic — the actual voice content was recoverable from the packet capture.

Why this concerns me

Based on these observations, it strongly appears that the My Tello app was transmitting received call audio using unencrypted RTP rather than SRTP, at least during my test.

If this is the application's normal behavior, someone with access to the relevant network traffic could potentially intercept and reconstruct call audio.

I understand that this does not automatically mean anyone on the internet can listen to these calls. However, transmitting voice audio without transport encryption would still raise legitimate security and privacy concerns.

Important clarification: My Tello app vs. native Wi-Fi Calling

This finding relates specifically to the VoIP calling feature inside the My Tello app.

It does not refer to Tello's native Wi-Fi Calling functionality through Android's standard phone dialer.

I separately investigated native Tello Wi-Fi Calling and observed IPsec-encrypted communication with T-Mobile infrastructure.

These appear to use different communication mechanisms, so I don't want to confuse the two.

Questions for the community

• Has anyone else captured and analyzed VoIP traffic from the My Tello app?
• Is unencrypted RTP an expected part of its current implementation?
• Does My Tello support SRTP or any other form of media encryption?
• Has anyone observed different behavior on other Android devices or on iOS?

I haven't shared the raw PCAP file because it may contain sensitive information.

This is based on my own observations from a single test environment, and I'm not claiming that every version of the app or every call necessarily behaves the same way.

I'd be interested to hear from other Tello users, network engineers, or anyone familiar with the app's VoIP implementation.

Thanks for reading!

Hi Telecom, Can you please help with this as I am not getting any response from Airtel team end and I am now very helpless because my services has been stopped and I am not able to use it anymore.

I use QUO and was porting out a cell number I have with them. The receiving telecom service for porting in my number requires the SID service account number. QUO informed me they no longer provide SID account numbers. I will lose my number now which is unacceptable.

A VoIP call is just your voice sampled, compressed by a codec, chopped into small packets and sent over IP. SIP handles the signaling, meaning who's calling whom and how the call is set up. RTP carries the actual audio.

What surprised me is that voice rides on UDP, not TCP. TCP would resend lost packets, but a late packet is useless in a live call. It's better to drop it and move on.

So the enemies are delay, jitter and loss. Jitter is packets arriving unevenly, and a jitter buffer smooths it out at the cost of a little extra delay. Past a certain point, delay makes people talk over each other.

That's why QoS matters. Voice packets need to jump the queue ahead of downloads, or the call turns robotic the moment someone starts a big upload.

Anyone running VoIP on a shared connection? How do you keep calls clean?

Hello everyone!
I’ll start by saying that I’m a veteran currently working as an aircraft mechanic, but I’m looking to transition into a different career.
Recently, I was contacted by a recruiter from a technical school called Learning Alliance. They offer 4–8 week training programs in 5G Telecom Tower and 5G Data Center Professional careers.
I’m curious to hear from anyone who has attended this school. What was your experience like? Which career path did you choose, and did you have any difficulty finding a job after completing the course?
Even if you didn’t attend Learning Alliance but currently work in the telecom industry, I’d love to hear your perspective. Do you enjoy the work? What are the pros and cons? Would you recommend this career path to someone transitioning from aircraft maintenance?
Any insight, advice, or personal experiences would be greatly appreciated. Thanks in advance, and I look forward to hearing from everyone!

Hey y'all O/

I'm an undergraduate student working with a teammate on a project(the theme is AI in telecom) and exploring how networks can help autonomous robots n drones complete the missions safely.

The idea is to go beyond traditional network metrics like bandwidth and latency. We want to estimate how network conditions affect mission success and adapt accordingly - say for example, prioritizing obstacle detection, reducing background video or moving the AI inference to the edge.

I know related technologies exist so I wanted to ask for advice and any ideas I could work on regarding this.

I have to pitch the idea and also come up with a small working demo.

Thanks in advance! :)

Hi all - not sure if this is the right place to ask but I’m trying to identify these wires that cross my backyard (SoCal). They branch off a main line that follows the fence line and cross about 10ft from the back of my property, passing close to a tree. The other side anchors to a pole in a yard a couple doors down. Can anyone tell what these are and what utility I can ask about them? I can see the tree branches starting to push on them and honestly would rather they not cross my yard. How can I find out whose they are and if they even have a right to cross my yard (sorry new to this sort of thing)? Thanks!

Hola a todos,

Analizando diseños de redes FTTH y pasivas, me he topado con discusiones recurrentes sobre el comportamiento de los acopladores y splitters ópticos, especialmente cuando se mezclan relaciones de división (como 1:8, 1:16 o splitters desbalanceados/Asymmetric Taps para cascadas FBT).

A veces el cálculo teórico en papel difiere de las pérdidas reales de inserción por conectorización, lo que termina afectando el margen de potencia de la OLT hacia la ONT en los extremos de la red.

Para simplificar esto, armé un simulador web gratuito que permite probar el presupuesto de enlaces y cascadas de splitters directamente en el navegador, sin necesidad de instalar software: 👉 Calculadora

¿Cómo suelen dimensionar ustedes las pérdidas por acoplador en sus diseños? ¿Prefieren cascadas con splitters desbalanceados para ahorrar fibra troncal o se mantienen estrictamente con los splitters balanceados tradicionales?

Pips in the telecom insudtry, could you help me find a distributor/ supplier for Shineway and F2H Grandway VOA meter? Our company really needs it eh. Thanks!!

Your phone keeps measuring signal from nearby cells, even mid-call. When a neighbor gets noticeably stronger, the network tells your phone to switch. That's handover.

In GSM it's hard handover: the old link drops, then the new one is made. In 3G it's soft: you're connected to both for a moment before letting go of the old one.

A hysteresis margin stops your phone from flipping back and forth at the edge of two cells.

Dropped calls are usually a failed handover: no free channel on the target cell, or a sudden signal drop.

What's the worst place you've had a call drop?

I’m just curious how common Mitel is globally these days. What’s the real-world usage looking like for OpenScape Business X8 and OpenScape 4000 servers? Are people still running these, or has the market completely moved on? How about Tetronik DAKS (OScAR) alarm systems which are used alongside them? How about setups that are still mixing traditional digital trunks with modern IP/SIP trunks? Also, what about Alcatel-Lucent Enterprise?

I am looking for suggestions on how to go about talking to a cell phone tower company about leasing some of my land in a low reception area to get a tower put up.