By Nisan Team  ·  Updated March 2026  ·  10 min read

How to Choose the Right ISP — A Technical Checklist Before You Buy Internet

Buying an internet connection sounds simple: pick a speed, pay, done. But two connections advertised as "100 Mbps" can perform completely differently once installed. The difference is in the technical details — the connection technology, whether the bandwidth is pure or shared, the contention ratio, your IP address type, latency, and uptime.

This guide explains every one of those terms in plain language, then gives you an exact checklist of what to ask any ISP before you pay. Use it in Bilimora or anywhere in India.

1. Internet Connection Technologies

The "pipe" that carries internet to your home decides most of your experience. Here are the main technologies you'll come across:

The simple rule: if FTTH fiber is available at your address, choose it. It beats every other technology on speed, stability and latency. We break down the wireless option in detail in fiber vs air fiber.

2. Bandwidth — Pure/Dedicated vs Shared

Bandwidth is how much data can flow per second — measured in Mbps (megabits per second). But the number alone doesn't tell you how it's delivered. This is where "pure bandwidth" comes in.

Pure / dedicated bandwidth

Pure (or dedicated) bandwidth means the speed is reserved only for you. A "100 Mbps dedicated" line gives you 100 Mbps at all times, no matter what your neighbours do. This is described as a 1:1 contention ratio. It's more expensive and mostly used by businesses running servers, heavy uploads, or critical operations.

Shared bandwidth & contention ratio

Most home broadband is shared. A single large pipe is split among many customers. The contention ratio tells you how many:

• 1:1 — dedicated, yours alone (business grade)
• 1:8 — up to 8 homes may share the line
• 1:16 / 1:32 — more sharing, more chance of evening slowdowns

A lower contention ratio = more consistent speed, especially at busy 8–11 PM hours. A good home ISP keeps enough capacity so shared plans still deliver full speed almost all the time.

3. Understanding Speed the Right Way

Mbps vs MBps

Plans are sold in Mbps (megabits). File sizes are in MB (megabytes). 8 bits = 1 byte, so a 100 Mbps line downloads at about 12.5 MB per second. Providers who quote "MB" to look bigger are being misleading. More on units in our Mbps guide.

Symmetrical vs asymmetrical

Most home plans are asymmetrical — fast download, slower upload (e.g. 100 down / 50 up). That's fine for browsing and streaming. If you upload a lot (YouTube creators, cloud backups, CCTV, video calls), ask about upload speed specifically, or a symmetrical plan (equal up and down). See internet for creators.

FUP (the hidden cap)

FUP (Fair Usage Policy) is a data cap that throttles your speed after a limit. Always ask whether a plan is truly unlimited or has an FUP. Nisan plans are genuinely unlimited — details in unlimited internet plans.

4. Your IP Address — What to Know

An IP address is your connection's address on the internet. There are a few types worth understanding before you buy:

Dynamic vs static IP

• Dynamic IP — changes from time to time. This is the default for homes and works for everything: browsing, streaming, gaming, video calls.
• Static IP — a fixed, unchanging address. Needed only if you host a server, want remote access to your home CCTV/NAS, run a VPN into your home, or have work that requires a fixed address. It's usually a paid add-on.

Public vs private & CGNAT

Your public IP is what the internet sees; your private IPs (like 192.168.x.x) are your devices at home. Some ISPs put many users behind one public IP using CGNAT (Carrier-Grade NAT) to save addresses. CGNAT is fine for normal use but can block remote CCTV access, port forwarding and some gaming. If you need remote access, ask: "Do you use CGNAT, and can I get a real public or static IP?"

IPv4 vs IPv6

IPv4 is the older address format (running out globally); IPv6 is the newer, near-unlimited one. Good ISPs support both. For most users it makes no visible difference — but IPv6 support is a sign of a modern network.

5. Latency, Jitter, Packet Loss & Uptime

Speed isn't everything. For calls, gaming and video these matter just as much:

• Latency (ping): delay in milliseconds. Lower is better. Fiber gives ~5–20 ms; good for gaming and calls. High ping causes lag even on "fast" connections.
• Jitter: variation in latency. High jitter makes video calls stutter. Fiber keeps jitter low.
• Packet loss: data that never arrives, causing freezes and drops. Should be near zero.
• Uptime / SLA: how often the connection is actually working. Ask about typical uptime and how fast faults are fixed.

You can check your own numbers any time with our free speed test — note the download, upload and ping figures.

6. The Pre-Purchase Checklist — What to Ask

Before you pay any ISP, run through these questions. A good provider answers all of them clearly:

1. Technology: Is it FTTH fiber, cable, DSL or wireless at my exact address?
2. Real speed: What download and upload speed will I actually get?
3. Bandwidth type: Is it shared or dedicated? What's the contention ratio?
4. Data cap: Is it truly unlimited, or is there an FUP limit?
5. Latency: What's typical ping? (important for gaming & calls)
6. Uptime & support: What's the uptime, and how fast are faults fixed? Local team or call centre?
7. IP address: Dynamic or static? Do you use CGNAT? Is a static IP available if I need it?
8. Total price: Is GST included? Any hidden setup or activation fees?
9. Installation & router: Are installation and the WiFi router free?
10. Contract & refund: Any lock-in? Is there a money-back guarantee if I'm not satisfied?
11. Coverage: How many customers do you already serve in my area?
12. Support hours: Are you available on Sundays and holidays?

How Nisan Answers This Checklist

Frequently Asked Questions