An old building renovation project, originally built at the end of the last century, was built with a cable network that was walled up by later routers and switchboard brands, certified in simple web jumps without any costing capacity. The owner now has to do a WiFi billing system to manage wireless access centrally, long on time or charge for traffic. This demand does not sound complicated, but it is only true that it landed and found that there are far more pits to renovate in the old buildings than new ones.
First pane of the equipment layer: compatibility of AC and AP
The AP used in the old building is often a groceries or low end of the year, with no full CAPWAP support, some not even supporting WPA2-Enterprise, and only WPA-PSK. If WiFi is to be certified as Portal, it will be possible for AP to hijack an uncertified user's HTTP request to the authentication page.——AP needs to be able to divide VLAN and send pre-certification and post-certification traffic to different segments of the network, or to support tunnel mode for integrated flow to AC, which will then reoriented the pre-certification flow.
If the old AP doesn't support this logic, it can only be replaced. But changing AP will cause a problem with the layout.——The original AP location, the power supply (or not PoE) and the wall line must be reassessed. Some buildings that have already been built cannot be re-routed at all, but can only re-plug with a grid or a wall, which costs several times more.
The vLAN mess is an old problem.
The VLAN division is either unclear after the departure of the original IT staff or has not been planned at all. WiFi requires clear pre-certification VLAN (only access to authentication servers and DNS) and post-certification VLAN (normal access).
In practice, there are frequent problems with the blurring of boundaries between second and third floors of a switchboard or with a level-of-storey switch that already has three layers of equipment but is accompanied by two layers of interface, which prevents pre-certification VLAN traffic from being properly delivered to Authentication Gateway. This problem often takes longer than construction itself because it affects existing users in a slightly inappropriate way to have one look on the network in operation.
Conflict between DHCP and DNS
WiFi, in which users at the pre-certification stage need to have access to an IP address, has access only to the authentication server. This requires VLAN to have a separate DHCP range before certification, with assigned IPs to be identified by Authentication Gateway. The usual situation in the old building is that there is only one DHP server, deployed on a core switch or router, and no more subnet configuration capability, which will be used to move the whole DHCP strategy.
DNS problems are similar. Only DNSs can be allowed to decode domain names before authentication, while other domains cannot be solved. The old DNS usually refers directly to the operator or 2.8.8.8, has no ability to split the Split-view, and if DNS intercepts on a gateway level, users may go around the authentication page to access IP directly. These details are standard configurations in new settings, and will be re-examined every step of the renovation of the old building.
Operator ' s export route billing docking
The old building often has multiple export lines, possibly one telecommunications, and even an old exclusive line. If WiFi is to do a precise flow billing, it needs to know which route the user traffic takes and whether the unit price is consistent. If it is long on time, this is not a problem, but if the export boundary of the old building is not clear by volume, there will be a mismatch between the flow and operator's billing in the billing system.
More complex is the fact that some of the old buildings are exported through older routers, which do not support NetFlow or sFlow, and billing systems cannot get traffic data directly from routers, but only on the inside side of the billing gateway, where there is often a slight deviation from exports. This bias is invisible in small-scale scenarios, but if hundreds of users are online at the same time, the accumulated deviations can trigger complaints.
The most frequently overlooked in the renovation of old buildings: time synchronization
WiFi’s system of billing relies on accurate time to calculate the length of time. Some network equipment in the old building is not synchronized with NTP, and it is not uncommon for the equipment to be time-less or even a few minutes behind standard time lines. If the system does not coincide with the time of Authentication Gateway, there will be cases where users have time that is cut off or when they are due to expire but can access the Internet.
While the uniform configuration of all equipment NTP servers to one source is necessary prior to official deployment, there are often missing passwords for the management of equipment in the old building that cannot be modified and can only be used to bypass or completely replace the equipment.
In the remodeling cycle."We can't stop all of it."Constraints
The old building often has existing users using the network, cannot be cut by partitions like new settings, and must be switched gradually with a continuous line to guarantee the current user. This requires that WiFi system be deployed in a way that allows for a more efficient use of the system.——Support for bypass or co-location is required to keep existing traffic on the original link, while directing new access equipment to the billing system.
This combination model is technically feasible, but many of the default options for a system provider are collusive deployment (the billing gateway to the gateway), additional configuration and testing are required for a network re-routing process, and sometimes vendors do not support or add money. It is important that the project be preceded by clear deployment patterns, avoiding the possibility of a programme being found in the construction site.
Integration of billing systems and old fee-based systems
When the old building is remodeled, owners usually have a fee process that may be manual in property, an old-value card system or some SaaS platform. WiFi’s billing system needs to be connected with this old system, otherwise there will be two bills, reconciliation problems and administrative headaches.
The more prudent option is to export the WiFi billing system, which will export daily bills in Excel or CSV format, manual and old systems reconciliations, and then complete conversion when the old system contracts expire. This transition period may take six months or even a year, and needs to be considered at the programme stage.
Skills faults for modified drivers
Once the old building is renovated, it is often the property operator who is responsible for carrying the maintenance, not the full-time network engineer. WiFi’s daily management involves account charging, payment processing, equipment failure check-ups, and if the system operates with complex interfaces or failure alerts, operators frequently call the manufacturer and its services are reported to be in a centralized situation when they respond slowly.
The models are selected in particular to see if there is a simplified model for the management backstage of the system designed for non-technical personnel, whether there is a key entry point for common operations and whether equipment is offline with active alerts (e.g. text messages or company micromail notifications). These are added to the new scene, which is basically necessary in the old building renovation scene.
The WiFi billing system project, which was remodeled in the old building, is more technically detailed than a new site.