A dipole antenna most commonly refers to a half-wavelength (/2) dipole. The physical antenna (not the package that it is in) is constructed of conductive elements whose combined length is about half of a wavelength at its intended frequency of operation. This is a simple antenna that radiates its energy out toward the horizon (perpendicular to the antenna). The patterns shown are those resulting from a perfect dipole formed with two thin wires oriented vertically along the z axis.

HSRP v1 allow only 265 group numbers.
HSRP v2 allow 4096 group number.

CoPP applies to all packets that punt to the route processor for handling.
http://www.cisco.com/c/en/us/about/security-center/copp-best-practices.html