Firewall
Definitie pe care am gasit-o pe Net:
A system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.
There are several types of firewall techniques:
Packet filter: Looks at each packet entering or leaving the network and accepts or rejects it based on user-defined rules. Packet filtering is fairly effective and transparent to users, but it is difficult to configure. In addition, it is susceptible to IP spoofing.
Application gateway: Applies security mechanisms to specific applications, such as FTP and Telnet servers. This is very effective, but can impose a performance degradation.
Circuit-level gateway: Applies security mechanisms when a TCP or UDP connection is established. Once the connection has been made, packets can flow between the hosts without further checking.
Proxy server: Intercepts all messages entering and leaving the network. The proxy server effectively hides the true network addresses.
In practice, many firewalls use two or more of these techniques in concert.
A firewall is considered a first line of defense in protecting private information. For greater security, data can be encrypted.
Eu folosesc un firewall gratuit, de la ZoneLabs, care se numeste ZoneAlarm si sunt destul de multumit de el.
http://www.zonelabs.com/store/content/company/products/znalm/freeDownload.jsp
Nu mi-am dat inca seama daca/cu cat incetineste accesul la Internet - poate ma lamureste si pe mine cineva. Si poate mai scrieti ce firewall-uri folositi voi.
Salutari!
Raspunsuri
joxy spune:
In afara de firewall-ul de pe serverul ISP-ului, de cel de pe Serverul firmei...
am instalat pe pc, de la symantec, Norton Personal Firewall.
Cu respect,
Florin
sk_bruce spune:
ipchains, iptables... sunt free si bune :)
PS. Ofc (of course) nu se configureaza prin Micro$oft Drag&Drop Advanced Technology...
xenocid spune:
sk_bruce nu rade de 'faierolu' de windows...
buun deci pina acum sintem 2...
hai sa mai recrutam...
Tata Alin
britdi spune:
Am si eu o intrebare: cum se poate inlatura un firewall instalat de provider ? Le-am spus ca ne-a dat totul peste cap: programele de chat, camera web nu mai merge, transferul de files nici atit... :(
joxy spune:
Briti... nu prea poti inlatura un firewall de pe un server la care nu ai access, doar daca nu ai cunostinte de cracker...sau vreun prieten acolo.
Dar poti cauta programe care sa ocoleasca acest firewall.. si in loc sa se lege pe porturile inkise.. sa treaca pe cele care au mai ramas deskise.
Acum, mai este o problema.. clientul nostru stapanul nostru...
"ori ne dati drumul la toate porturile.. ori cautam un alt ISP-ist".. asta daca ai autoritatea necesara... daca o aveai nu cred ca mai intrebai..
Cu respect,
Florin