Adder Technology AVX4016IP ユーザーズマニュアル

The.IP.access.control.function.uses.a.standard.IP.address.and.a.net.mask.
notation.to.specify.both.single.locations.and.ranges.of.addresses..In.order.to.
use.this.function.correctly,.you.need.to.calculate.the.mask.so.that.it.accurately.
encompasses.the.required.address(es).

Single locations
Some.of.the.simplest.addresses.to.allow.or.deny.are.single.locations..In.this.case.
you.enter.the.required.IP.address.into.the.‘Network/Address’.field.and.simply.
enter.the.‘Mask’.as.

255.255.255.255.(255 used throughout the mask means 

that every bit of the address will be compared and so there can only be one 
unique address to match the one stated in the ‘Network/Address’ field).

All locations
The.other.easy.setting.to.make.is.ALL.addresses,.using.the.mask.

0.0.0.0..As.

standard,.the.IP.access.control.section.includes.the.entry:.+

0.0.0.0/0.0.0.0 

The.purpose.of.this.entry.is.to.include.all.IP.addresses..It.is.possible.to.similarly.
exclude.all.addresses,.however,.take.great.care.not.to.do.this.as.you.instantly.
render.all.network.access.void..There.is.a.

.should.this.occur..

Address ranges
Although.you.can.define.ranges.of.addresses,.due.to.the.way.that.the.mask.
operates,.there.are.certain.restrictions.on.the.particular.ranges.that.can.be.set..
For.any.given.address.you.can.encompass.neighbouring.addresses.in.blocks.of.
either.2,.4,.8,.16,.32,.64,.128,.etc..and.these.must.fall.on.particular.boundaries..
For.instance,.if.you.wanted.to.define.the.local.address.range:.
192.168.142.67 to 192.168.142.93.
The.closest.single.block.to.cover.the.range.would.be.the.32.addresses.from:.
192.168.142.64 to 192.168.142.95..
The.mask.needed.to.accomplish.this.would.be:.

255.255.255.224..

When.you.look.at.the.mask.in.binary,.the.picture.becomes.a.little.clearer..The.
above.mask.has.the.form:.

11111111.11111111.11111111.

11100000

.

Ignoring.the.initial.three.octets,.the.final.six.zeroes.of.the.mask.would.ensure.
that.the.32.addresses.from..64.(01000000).to..95.(01011111).would.all.be.
treated.in.the.same.manner..See.

.for.

details........
When.defining.a.mask,.the.important.rule.to.remember.is:

There must be no ‘ones’ to the right of a ‘zero’..

For.instance,.(ignoring.the.first.three.octets).you.could.not.use.a.mask.that.had.

11100110 

because.this.would.affect.intermittent.addresses.within.a.range.in.an.

impractical.manner..The.same.rule.applies.across.the.octets..For.example,.if.you.
have.zeroes.in.the.third.octet,.then.all.of.the.fourth.octet.must.be.zeroes..

The.permissible.mask.values.(for.all.octets).are.as.follows:.

Mask octet 

Binary 

Number of addresses encompassed

255 

11111111 

254 

11111110.

2 addresses.

252 

11111100.

248 

11111000.

240 

11110000.

224 

11100000.

192 

11000000.

128 

10000000.

0 

00000000.

If.the.access.control.range.that.you.need.to.define.is.not.possible.using.one.
address.and.one.mask,.then.you.could.break.it.down.into.two.or.more.entries..
Each.of.these.entries.could.then.use.smaller.ranges.(of.differing.sizes).that,.
when.combined.with.the.other.entries,.cover.the.range.that.you.require.
For.instance,.to.accurately.encompass.the.range.in.the.earlier.example:
192.168.142.67 to 192.168.142.93.
You.would.need.to.define.the.following.six.address.and.mask.combinations.in.
the.IP.access.control.section:

Network/address entry  Mask entry

192.168.142.67 

255.255.255.255 

192.168.142.68 

255.255.255.252 

192.168.142.72 

255.255.255.248 

192.168.142.80 

255.255.255.248 

192.168.142.88 

255.255.255.252 

192.168.142.93 

255.255.255.255