We claim:
1. A method of synchronizing firewalls in a communication system comprising a server farm connected to the Internet network by an Internet front-end including at least an Internet access router, said server farm comprising at least two customer cabinets with each customer cabinet including at least a WEB server and server farm resources enabling users connected to the Internet to access the WEB servers in said customer cabinets, and at least two firewalls for controlling communication between users and one of said WEB servers, said firewalls using a Virtual Router Redundancy Protocol (VRRP) to set up as primary interface firewall the firewall which owns the primary interface of the VRRP group of interfaces to at least one customer cabinet;
said method comprising steps of:
a) initializing, in a secondary interface firewall, a synchronization message exchange with a primary interface firewall after receiving a packet for a connection, the state of which is incompatible with said received packet, or after standard firewall processing of a packet corresponding to a new connection has been completed, and
b) registering a connection state in a common connection table maintained in firewalls that said connection goes through if said connection is new or if said connection state has changed.
2. The method according to claim 1, wherein the step of initializing includes, after said secondary interface firewall has received a packet for a connection the state of which is incompatible with said received packet, the steps of:
requesting, from said secondary interface, for the state of said connection to the primary interface firewall, and
sending, from said primary interface firewall, a response message indicating the state of said incompatible connection to any other secondary interface firewall.
3. The method according to claim 2, wherein said step of registering includes for any secondary interface firewall, after receiving a response message indicating the state of said incompatible connection, the steps of:
registering in its common connection table the new state of said connection with said primary interface firewall as neighbor, and
setting the state of said connection in its firewall table to said new state.
4. The method according to claim 3, wherein the packet for which the connection state sent back by said primary interface firewall is the same as the local state for this connection in its firewall table is handed over to a firewall discard and log process.
5. The method according to claim 3, wherein the current state of said connection is registered in the common connection table of said primary interface firewall with said secondary interface firewall as neighbor after receiving the request from said secondary interface firewall.
6. The method according to claim 2, wherein said connection is removed from said common connection table and from said firewall table when the state of said connection sent by said primary interface firewall is zero.
7. The method according to claim 1, wherein said step of initializing includes when said secondary interface firewall has received a packet after standard firewall processing of a packet corresponding to a new connection has been completed, a step of notifying from said secondary interface firewall the state of said new connection to said primary interface firewall.
8. The method according to claim 7, wherein said step of registering includes, for said primary interface firewall, the steps of:
registering in its common connection table the notified state of said connection with said secondary interface firewall as neighbor, and
adding the connection set to said notified state to its firewall table.
9. The method according to claim 1, wherein a connection state notification is forwarded from any firewall to its neighbor firewalls whenever the state of a connection in said common connection table has changed after standard firewall processing of the packet in said firewall.
10. A computer program for synchronizing the firewalls in a communication system comprising instructions adapted to implement the method according to claim 1.
11. A communication system comprising a server farm which is connected to the Internet network by an Internet front-end including at least an Internet access router, said server farm comprising at least two customer cabinets with each customer cabinet including at least a WEB server and server farm resources enabling user connected to the Internet to access the WEB servers in said customer cabinets, and at least two firewalls for controlling communication between users and one of said WEB servers, said firewalls using a Virtual Router Redundancy Protocol (VRRP) to setup one of said firewalls as primary firewall through which is established communication between an Internet user and one of said customer cabinets, wherein each one of said firewalls is provided with a computer program according to claim 10.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A mask comprising at least one opening to guide light to a subject, a size of the opening being adjusted according to a distance between the mask and the subject.
2. The mask according to claim 1, wherein the light guided by the opening is linearly polarized light.
3. The mask according to claim 1, wherein a thickness of the opening is substantially identical to or greater than five times the distance between the mask and the subject.
4. The mask according to claim 1, wherein a width of the opening becomes narrow from a side of the opening to which the light is irradiated toward a side of the opening from which the light guided by the opening is emitted.
5. The mask according to claim 1, further comprising a total reflection layer formed on an inner wall of the opening.
6. The mask according to claim 1, wherein the subject has a curved surface, and the size of the opening is adjusted according to a radius of curvature of the curved surface.
7. The mask according to claim 6, wherein the curvature radius of the surface of the subject is 150 mm to 250 mm and the thickness of the opening is 5 mm to 20 mm.
8. An apparatus comprising:
a device to which a subject is mounted; and
a mask including at least one opening to guide the light to the subject, wherein a size of the opening is adjusted according to a distance between the mask and the subject.
9. The apparatus according to claim 8, wherein a thickness of the opening is substantially identical to or greater than five times the distance between the mask and the subject.
10. The apparatus according to claim 9, wherein the distance between the mask and the subject is greater than 0 mm and substantially identical to or less than 50 mm.
11. The apparatus according to claim 8, wherein the device is configured to mount the subject such that a surface of the subject has a curved shape, and the size of the opening of the mask is adjusted according to a radius of curvature of the subject.
12. The apparatus according to claim 11, wherein the curvature radius of the surface of the subject is 150 mm to 250 mm, and the thickness of the opening is 5 mm to 20 mm.
13. The apparatus according to claim 8, further comprising a light source to irradiate the light to the mask, the light source configured to form light linearly progressing only toward the mask.
14. The apparatus according to claim 13, wherein the light source comprises a short-arc discharge lamp.
15. The apparatus according to claim 13, wherein the light source comprises a plurality of light irradiation units arranged in two or more rows, and the light irradiation unit in one row and the light irradiation unit in another row adjacent to the row are arranged to overlap each other with misalignment.
16. The apparatus according to claim 13, further comprising a condenser configured to condense the light irradiated from the light source and to transfer the condensed light toward the mask.
17. The apparatus according to claim 13, further comprising a polarizing plate configured to generate linearly polarized light from the light irradiated from the light source and to transfer the linearly polarized light toward the mask.
18. A method of generating linearly progressing light, comprising:
irradiating light toward a mask including at least one opening to guide the light to a subject; and
guiding the light irradiated from the opening to the subject,
wherein a size of the opening is adjusted according to a distance between the mask and the subject.
19. The method according to claim 18, wherein a thickness of the opening is substantially identical to or greater than five times the distance between the mask and the subject.
20. The method according to claim 19, wherein the distance between the mask and the subject is maintained to be greater than 0 mm and substantially identical to or less than 50 mm.
21. The method according to claim 18, wherein the subject has a curved surface, and the size of the opening is adjusted according to a radius of curvature of the subject.
22. The method according to claim 21, wherein the curvature radius of the surface of the subject is 150 mm to 250 mm, and the thickness of the opening is 5 mm to 20 mm.
23. A method of manufacture a photo-aligning layer, comprising:
irradiating light toward a mask including at least one opening to guide the light to the photo-aligning layer; and
guiding the light irradiated from the opening to the photo-aligning layer,
wherein a size of the opening is adjusted according to a distance between the mask and the photo-aligning layer.
24. The method according to claim 23, wherein a thickness of the opening is substantially identical to or greater than five times the distance between the mask and the photo-aligning layer.
25. The method according to claim 24, wherein the distance between the mask and the photo-aligning layer is maintained to be greater than 0 mm and substantially identical to or less than 50 mm.
26. The method according to claim 23, wherein the photo-aligning layer has a curved surface, and the size of the opening of the mask is adjusted according to a radius of curvature of the photo-aligning layer.
27. The method according to claim 26, wherein the curvature radius of the surface of the photo-aligning layer is 150 mm to 250 mm, and the thickness of the opening is 5 mm to 20 mm.
28. The method according to claim 23, wherein the photo-aligning layer includes an photo-aligning compound having a functional group derived from one or more compound selected from the group consisting of azobenzene, styryl benzene, cumarine, chalcone, and cinnamic acid.
29. A photo-aligning layer manufactured using the method according to claim 23, wherein an area of a non-aligned portion is substantially identical to or less than 10% of a total area.
30. An optical filter comprising the photo-aligning layer according to claim 29 and a phase retardation layer formed on at least one surface of the photo-aligning layer.