ADSL2+ Price List

The first difference between these two services is their way of speed allocation. Volume-based services are currently available in two connection speed groups which called Special (from 2 Mbps to 16 Mbps) and basic (from 128 Kbps to 1 Mbps), whereas Non Volume-Based services are available in 4 fixed connection speeds (1, 2, 4 and 8 Mbps).
The second difference between these services is the amount of their monthly traffic. Non-volume-Based services have a higher amount of monthly traffic.
The third difference is the cost of extra traffic when the user exceeds the volume limit. In the Volume-based service, if the user approaches the volume limit, they must buy extra traffic based on the normal traffic tab, whereas, in Non-Volume-Based services, each extra Gigabyte costs 1,500 Toman.

Special offers have a guaranteed fixed connection speed of 1 Mbps with the possibility of increasing it up to 8 Mbps, whereas Volume-based services are available in two connection speed groups of special (from 2 Mbps to 16 Mbps) and basic (from 128 Kbps to 1 Mbps).
All the traffic of the Volume-Based services are added at once at the beginning of the period, while the data traffic of special offers is added monthly.
Some of the special offers are exclusive to new customers, while such limitation is not imposed on Volume-Based services.

The guaranteed connection speed of special Volume-Based services are 2 Mbps and are upgradable up to 16 Mbps. This means that the minimum speed is definitely 2 Mbps. But the speed is upgradable up to 16 Mbps provided the line is strong enough. Go to this address to get familiar with the differences between Bit and Byte.
It should be noted that the cost of these services is lower than the minimum guaranteed speed and even if the line is not strong enough, the subscriber will not endure any losses.

The defined services are designed with the goal of simplicity in choice and profitability; therefore, Volume-Based services are available with a 9 to 19 percent discount compared to the fee of the service’s minimum speed so as to fulfill both of the abovementioned goals.
Currently, instead of paying different fees for different connection speed levels, subscribers can receive a service with their desired speed by paying the fee of a lower speed level.

Non-Volume-Based services are similar to unlimited services but a service with an unlimited traffic volume is not currently available.

All of the traffic of the Volume-Based services are added at once at the beginning of the period, while the traffic of special offers is added monthly to the user’s account.

No, it can’t. The traffic of current special offers and services cannot normally be rolled over to the next billing period.