Festo SBO*-M-* Series, Electronic Manual

Page: 53 / 84

4 . Commissio n i ng
4− 5
F es t o P .B E−S BO −M−EN e n 0511 N H
4.2 Addressing in the Ethernet (basics)
Du e t o th e se p a r a t io n i nt o lo g ical a nd phy sical pr o t ocol la y e r s
(Eth e rn e t a nd T C P/IP), th e r e e x is t tw o typ es o f a ddr esses i n a
n e tw o rk:
a f i x e d Eth e rn e t a ddr ess (MA C −ID) f o r eac h d e v ice a nd
a n IP a ddr ess wh ic h is assi gn e d t o e v e ry d e v ice i n th e
n e tw o rk .
Be f o r e th e a pp lica t io n, d a t a a r e al w a y s se nt t o o r r ecei v e d
fr om a n IP a ddr ess. In o rd e r th a t th e d a t a r eac h th e r ecei v e r,
a co rr ela t io n m u s t b e c r ea t e d b e tw ee n th e lo g ical IP a ddr ess
a nd th e phy sical Eth e rn e t a ddr ess. Th e Addr ess R esol ut io n
Pr o t ocol ARP is u se d f o r th is purp ose : An ARP t a b le is sa v e d
i n eac h n e tw o rk P C. Th is t a b le lis t s th e r ele v a nt phy sical
Eth e rn e t a ddr ess f o r eac h IP a ddr ess i n th e n e tw o rk . If a n
Eth e rn e t a ddr ess is n o t lis t e d i n th e ARP t a b le , th e IP dr i v e r
ca n asce rt ai n i t w i th th e ai d o f a n ARP r e qu es t .
Eth e rn e t a ddr ess
(MA C −ID)
Th e un al t e r a b le w o r l dw i d e clea r Eth e rn e t a ddr ess (MA C −ID)
o f th e Com p ac t Visio n Sy s t em ca n b e f o und o n th e typ e
p la t e. In th is w a y y o u ca n clea r l y d is t i ngu is h th e d i ff e r e nt
Com p ac t Visio n Sy s t ems.
IP a ddr ess An IP a ddr ess as p e r s t a nd a rd IPv4 is u s u all y s p eci f ie d w i th
4 d ecimal nu m b e r s se p a r a t e d by p oi nt s (p e r 1 byt e ) .
Example of an IP address: 192.168.2.10
W i th a n IP a ddr ess , a n e tw o rk as w ell as a n i nd i v i du al s t a t io n
i n th e n e tw o rk ca n b e a ddr esse d . Th e IP a ddr ess th e r e f o r e
co nt ai n s :
th e n e tw o rk ID ( s p eci f ies th e a ddr ess o f a n e tw o rk) a nd
th e h os t ID ( s p eci f ies th e a ddr ess o f a n i nd i v i du al s t a t io n
i n th is n e tw o rk) .