Regional service. VPC = virtual network inside AWS. Private and isolated by default.

Default VPC

max 1 per region. can be deleted and recreated. 1 per region created automatically. gets 1 default cidr (172.31.0.0/16) cidr split into subnets for different azs. (/20 subnets) Subnets assign public IPv4 address. InternetGW , SG and NACL. Security features SG and NACL.

Custom VPCs

created manually. more flexible. can have multiple cidrs.

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