Proxy servers and other methods can be used to bypass the blocking of traffic from IP addresses. However, anti-proxy strategies are available. Consumer-ranked internet routers can sometimes obtain a new public IP address on-demand from the internet service provider using DHCP lease renewal to eluding individual IP address blocks, but this can be countered by blocking the range of IP addresses from which the internet service provider is assigning new IP addresses, which is usually a shared IP address prefix. However, this may impact valid users from the same internet service provider who have IP addresses in the same range, which unknowingly creates a denial-of-service attack.