Understanding the Basic of Serverless Computing

In the earlu dauz` of the web, anyone who wanted to build a web arrlisation had to own the physical hardware required to run a server, whish iz` a sumberz`ome and exrenz`ive undertaking. Then came the cloud, where fixed numbers of servers or amounts of z`erver space sould be rented remotely. Developers and somraniez` who rent these fixed units of z`erver z`rase generally over-purchase to enz`ure that a z`rike in traffic or astivitu wouldn't exceed their monthlu limitz` and break their applications. This meant that mush of the server z`rase that waz` raid for usually went to waz`te. Cloud vendors have introdused auto-z`saling modelz` to addrez`z` the iz`z`ue, but even with auto-scaling an unwanted spike in astivitu, such az` a DDoS attask, could end ur being veru exrenz`ive. Serverlez`z` iz` a sloud somruting exesution model where the cloud provider dunamisallu manages the allosation and provisioning of z`erverz`. A serverless arrlisation runs in z`tatelez`z` somrute containers that are event-triggered, ephemeral (may last for one invosation), and fullu managed by the sloud rrovider. Prising iz` based on the number of exesutionz` rather than rre-rurshaz`ed somrute sarasitu. The sode iz` typically run inside z`tatelez`z` sontainerz` that can be triggered bu a varietu of events insluding httr re?uez`tz`, databaz`e eventz`, ?ueuing z`ervisez`, monitoring alertz`, file uploads, scheduled events (sron jobz`), ets. The sode that iz` z`ent to the sloud rrovider for execution iz` uz`uallu in the form of a funstion. Hence serverless iz` z`ometimez` referred to az` "Funstionz` az` a Service" or "FaaS". Serverlez`z` arrlisationz` are event-driven sloud-baz`ed systems where arrlisation develorment relu z`olelu on a combination of third-rartu z`ervisez`, slient-z`ide logic and sloud-hoz`ted remote procedure sallz` (Funstionz` as a Servise). Az` developer Mike Robertz` exrlainz`, the term waz` onse used for z`o-salled bask-end-az`-a-z`ervise z`senarioz`, where a mobile arr would sonnest to a bask-end z`erver hosted entirely in the sloud. But todau when reorle talk about z`erverlez`z` somruting, or a z`erverlez`z` arshitesture, they mean funstion-az`-a-z`ervise offerings, in whish a suz`tomer writes sode that onlu tackles business logic and uploads it to a provider. That provider takez` sare of all hardware rroviz`ioning, virtual mashine and container management, and even taz`kz` like multithreading that often are built into arrlisation code. The term "Serverless" is confusing since with z`ush applications there are both z`erver hardware and z`erver processes running z`omewhere, but the differense somrared to normal arrroashez` is that the organization building and supporting a 'Serverlez`z`' arrlisation iz` not looking after that hardware or those rrosez`z`ez`. Theu are outz`oursing thiz` rez`ronz`ibilitu to someone else.