Adder Technology AVX4016 사용자 설명서

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Ports
If.you.accept.the.analogy.of.
.being.rather.like.telephone.numbers,.
then.think.of.ports.as.extension.numbers..In.a.company.of.any.size,.you.
generally.wouldn’t.expect.the.accounts.department.to.share.the.same.telephone.
with.the.technical.department..Although.their.calls.may.all.be.related.to.the.
same.company,.they.concern.very.different.aspects.of.that.company..
It.is.the.same.with.IP.network.connections..Although.you.have.only.one.network.
link.into.your.computer.and.only.one.IP.address.(phone.number),.you.are.
probably.performing.many.different.tasks.through.that.one.link,.often.at.the.
same.time..Thus,.when.you.browse.the.web.your.outgoing.requests.and.the.
incoming.information.are.all.channelled.through.port.80..When.you.send.an.
email,.it.travels.through.port.25.and.when.you.transfer.files.you.are,.without.
knowing.it,.using.port.20.
At.the.“border.crossing”.between.the.wider.Internet.and.every.local.network.
attached.to.it,.there.is.a.router.that.is.usually.combined.with.a.firewall..One.of.
its.main.tasks.is.to.direct.incoming.traffic.to.the.correct.place.within.its.local.
network..A.key.piece.of.information.to.help.it.do.this.is.the.port.number:.
Security issues with ports
The.settings.of.port.numbers.become.important.when.the.AdderView.CATx.IP.
is.situated.behind.a.network.firewall..In.order.for.a.remote.VNC.viewer.or.web.
browser.to.make.contact.with.your.AdderView.CATx.IP,.it.is.necessary.for.the.
firewall.to.allow.communication.through.a.particular.numbered.port.to.occur..
One.specific.function.of.firewalls.is.to.restrict.access.to.ports.in.order.to.prevent.
malicious.attackers.using.them.as.a.route.into.your.network..Every.new.port.that.
is.opened.offers.a.new.possibility.for.hackers.and.so.the.number.of.accessible.
ports.is.purposefully.kept.to.a.minimum..In.such.cases,.it.may.be.advantageous.
to.change.one.or.both.AdderView.CATx.IP.ports.to.use.the.same.number..The.
other.alternative.is.to.place.the.AdderView.CATx.IP.unit.outside.the.firewall.and.
take.full.advantage.of.its.secure.operation.features.–.see.
.for.
details.
IMPORTANT: The correct configuration of routers and firewalls requires 
advanced networking skills and intimate knowledge of the particular network. 
Adder Technology cannot provide specific advice on how to configure your 
network devices and strongly recommend that such tasks are carried out by a 
qualified professional.
AdderView.CATx.IP.has.
the.local.IP.address:.
192.168.0.3
User.with.VNC.viewer.accesses.
IP.address:.129.7.1.10.(this.
automatically.uses.port.5900)..
Router/firewall address: 9...0
Router.is.programmed.to.send.port.5900.
VNC.traffic.to.local.address.192.168.0.3.
and.port.80.web.traffic.to.local.address.
192.168.0.42
.
User.accesses.the.company.
website.at:.129.7.1.10.(this.
automatically.uses.port.80)..
Web.server.has.the.local.
IP.address:.192.168.0.42